![USMC-100414-M-5241M-001](https://upload.wikimedia.org/wikipedia/commons/4/4c/USMC-100414-M-5241M-001.jpg)
A shell, in a
military
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...
context, is a
projectile
A projectile is an object that is propelled by the application of an external force and then moves freely under the influence of gravity and air resistance. Although any objects in motion through space are projectiles, they are commonly found in ...
whose payload contains an
explosive
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An expl ...
,
incendiary, or other
chemical
A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., wi ...
filling. Originally it was called a bombshell, but "shell" has come to be unambiguous in a military context. Modern usage sometimes includes large solid
kinetic projectile
A kinetic energy weapon (also known as kinetic weapon, kinetic energy warhead, kinetic warhead, kinetic projectile, kinetic kill vehicle) is a weapon based solely on a projectile's kinetic energy instead of an explosive or any other kind of payl ...
s that is properly termed shot. Solid shot may contain a pyrotechnic compound if a
tracer or spotting charge is used.
All explosive- and incendiary-filled projectiles, particularly for
mortars, were originally called ''grenades'', derived from the
French
French (french: français(e), link=no) may refer to:
* Something of, from, or related to France
** French language, which originated in France, and its various dialects and accents
** French people, a nation and ethnic group identified with Franc ...
word for
pomegranate
The pomegranate (''Punica granatum'') is a fruit-bearing deciduous shrub in the family Lythraceae, subfamily Punicoideae, that grows between tall.
The pomegranate was originally described throughout the Mediterranean Basin, Mediterranean re ...
, so called because of the similarity of shape and that the multi-seeded fruit resembles the powder-filled, fragmentizing bomb. Words cognate with ''grenade'' are still used for an artillery or mortar projectile in some European languages.
Shells are usually large-caliber projectiles fired by
artillery
Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...
,
armored fighting vehicle
An armoured fighting vehicle (AFV) is an armed combat vehicle protected by armour, generally combining operational mobility with offensive and defensive capabilities. AFVs can be wheeled or tracked. Examples of AFVs are tanks, armoured cars, ...
s (e.g.
tank
A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and good battlefield mobility provided by tracks and a powerful engin ...
s,
assault gun
Assault gun (from german: Sturmgeschütz - "storm gun", as in "storming/assaulting") is a type of self-propelled artillery which uses an infantry support gun mounted on a motorized chassis, normally an armored fighting vehicle, which are designed ...
s, and
mortar carrier
A mortar carrier, or self-propelled mortar, is a self-propelled artillery piece in which a mortar is the primary weapon. Simpler vehicles carry a standard infantry mortar while in more complex vehicles the mortar is fully integrated into the ...
s),
warship
A warship or combatant ship is a naval ship that is built and primarily intended for naval warfare. Usually they belong to the armed forces of a state. As well as being armed, warships are designed to withstand damage and are usually faster a ...
s, and
autocannon
An autocannon, automatic cannon or machine cannon is a fully automatic gun that is capable of rapid-firing large-caliber ( or more) armour-piercing, explosive or incendiary shells, as opposed to the smaller-caliber kinetic projectiles (bull ...
s. The shape is usually a
cylinder
A cylinder (from ) has traditionally been a three-dimensional solid, one of the most basic of curvilinear geometric shapes. In elementary geometry, it is considered a prism with a circle as its base.
A cylinder may also be defined as an infin ...
topped by an
ogive
An ogive ( ) is the roundly tapered end of a two-dimensional or three-dimensional object. Ogive curves and surfaces are used in engineering, architecture and woodworking.
Etymology
The earliest use of the word ''ogive'' is found in the 13th c ...
-tipped
nose cone
A nose cone is the conically shaped forwardmost section of a rocket, guided missile or aircraft, designed to modulate oncoming airflow behaviors and minimize aerodynamic drag. Nose cones are also designed for submerged watercraft such a ...
for good
aerodynamic
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dyn ...
performance
A performance is an act of staging or presenting a play, concert, or other form of entertainment. It is also defined as the action or process of carrying out or accomplishing an action, task, or function.
Management science
In the work place ...
, and possibly with a tapered
boat tail; but some specialized types differ widely.
Background
Gunpowder is a
low explosive
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An expl ...
, meaning it will not create a concussive,
brisant explosion unless it is contained, as in a modern-day
pipe bomb
A pipe bomb is an improvised explosive device which uses a tightly sealed section of pipe (material), pipe filled with an explosive material. The containment provided by the pipe means that simple Explosive material#Low explosives, low explosi ...
or
pressure cooker bomb
A pressure cooker bomb is an improvised explosive device (IED) created by inserting explosive material into a pressure cooker and attaching a blasting cap into the cover of the cooker.
Pressure cooker bombs have been used in a number of attacks ...
. Early
grenades
A grenade is an explosive weapon typically thrown by hand (also called hand grenade), but can also refer to a shell (explosive projectile) shot from the muzzle of a rifle (as a rifle grenade) or a grenade launcher. A modern hand grenade gene ...
were hollow cast-iron balls filled with gunpowder, and "shells" were similar devices designed to be shot from artillery in place of solid cannonballs ("shot").
Metonymically
Metonymy () is a figure of speech in which a concept is referred to by the name of something closely associated with that thing or concept.
Etymology
The words ''metonymy'' and ''metonym'' come from grc, μετωνυμία, 'a change of name' ...
, the term "shell", from the casing, came to mean the entire
munition
Ammunition (informally ammo) is the material fired, scattered, dropped, or detonated from any weapon or weapon system. Ammunition is both expendable weapons (e.g., bombs, missiles, grenades, land mines) and the component parts of other weapo ...
.
In a gunpowder-based shell, the casing was intrinsic to generating the explosion, and thus had to be strong and thick. Its fragments could do considerable damage, but each shell broke into only a few large pieces. Further developments led to shells which would fragment into smaller pieces. The advent of
high explosives
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An exp ...
such as
TNT
Trinitrotoluene (), more commonly known as TNT, more specifically 2,4,6-trinitrotoluene, and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagen ...
removed the need for a pressure-holding casing, so the casing of later shells only needs to contain the munition, and, if desired, to produce shrapnel. The term "shell," however, was sufficiently established that it remained as the term for such munitions.
Hollow shells filled with gunpowder needed a fuse that was either impact triggered (
percussion
A percussion instrument is a musical instrument that is sounded by being struck or scraped by a beater including attached or enclosed beaters or rattles struck, scraped or rubbed by hand or struck against another similar instrument. Exc ...
) or time delayed.
Percussion fuses with a spherical projectile presented a challenge because there was no way of ensuring that the impact mechanism contacted the target. Therefore, ball shells needed a time fuse that was ignited before or during firing and burned until the shell reached its target.
Early shells
![Chinese Cannon](https://upload.wikimedia.org/wikipedia/commons/c/c6/Chinese_Cannon.JPG)
Cast iron shells packed with gunpowder have been used in warfare since at least early 13th century China. Hollow, gunpowder-packed shells made of
cast iron
Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
used during the Song dynasty (960-1279) are described in the early
Ming Dynasty
The Ming dynasty (), officially the Great Ming, was an Dynasties in Chinese history, imperial dynasty of China, ruling from 1368 to 1644 following the collapse of the Mongol Empire, Mongol-led Yuan dynasty. The Ming dynasty was the last ort ...
Chinese
Chinese can refer to:
* Something related to China
* Chinese people, people of Chinese nationality, citizenship, and/or ethnicity
**''Zhonghua minzu'', the supra-ethnic concept of the Chinese nation
** List of ethnic groups in China, people of va ...
military manual ''
Huolongjing
The ''Huolongjing'' (; Wade-Giles: ''Huo Lung Ching''; rendered in English as ''Fire Drake Manual'' or ''Fire Dragon Manual''), also known as ''Huoqitu'' (“Firearm Illustrations”), is a Chinese military treatise compiled and edited by Jiao ...
'', written in the mid 14th century.
[Needham, Joseph. (1986). Science and Civilization in China: Volume 5, Chemistry and Chemical Technology, Part 7, Military Technology; the Gunpowder Epic. Taipei: Caves Books Ltd. Pages 24–25, 264.] The ''History of Jin'' 《金史》 (compiled by 1345) states that in 1232, as the Mongol general
Subutai
Subutai (Classical Mongolian: ''Sübügätäi'' or ''Sübü'ätäi''; Modern Mongolian: Сүбээдэй, ''Sübeedei''. ; ; c. 1175–1248) was a Mongol general and the primary military strategist of Genghis Khan and Ögedei Khan. He directed m ...
(1176–1248) descended on the Jin stronghold of
Kaifeng
Kaifeng () is a prefecture-level city in east-central Henan province, China. It is one of the Eight Ancient Capitals of China, having been the capital eight times in history, and is best known for having been the Chinese capital during the Nort ...
, the defenders had a "
thunder crash bomb
The thunder crash bomb (), also known as the heaven-shaking-thunder bomb, was one of the first bombs or hand grenades in the history of gunpowder warfare. It was developed in the 12th-13th century Song and Jin dynasties. Its shell was made of cast ...
" which "consisted of gunpowder put into an iron container ... then when the fuse was lit (and the projectile shot off) there was a great explosion the noise whereof was like thunder, audible for more than thirty miles, and the vegetation was scorched and blasted by the heat over an area of more than
half a ''mou''. When hit, even
iron armour
Iron armour was a type of naval armour used on warships and, to a limited degree, fortifications. The use of iron gave rise to the term ironclad as a reference to a ship 'clad' in iron. The earliest material available in sufficient quantities for ...
was quite pierced through."
[Needham, Joseph. (1986). Science and Civilization in China: Volume 5, Chemistry and Chemical Technology, Part 7, Military Technology; the Gunpowder Epic. Taipei: Caves Books Ltd. Pages 24–25, 264.] Archeological examples of these shells from the 13th century Mongol invasions of Japan have been recovered from a shipwreck.
Shells were used in combat by the
Republic of Venice
The Republic of Venice ( vec, Repùblega de Venèsia) or Venetian Republic ( vec, Repùblega Vèneta, links=no), traditionally known as La Serenissima ( en, Most Serene Republic of Venice, italics=yes; vec, Serenìsima Repùblega de Venèsia, ...
at Jadra in 1376. Shells with fuses were used at the 1421 siege of St Boniface in
Corsica
Corsica ( , Upper , Southern ; it, Corsica; ; french: Corse ; lij, Còrsega; sc, Còssiga) is an island in the Mediterranean Sea and one of the 18 regions of France. It is the fourth-largest island in the Mediterranean and lies southeast of ...
. These were two hollowed hemispheres of stone or bronze held together by an iron hoop.
[Hogg, p. 164.] At least since the 16th century grenades made of ceramics or glass were in use in Central Europe. A hoard of several hundred ceramic grenades dated to the 17th century was discovered during building works in front of a bastion of the Bavarian city of
Ingolstadt
Ingolstadt (, Austro-Bavarian: ) is an independent city on the Danube in Upper Bavaria with 139,553 inhabitants (as of June 30, 2022). Around half a million people live in the metropolitan area. Ingolstadt is the second largest city in Upper Bav ...
,
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
. Many of the grenades contained their original black-powder loads and igniters. Most probably the grenades were intentionally dumped in the moat of the bastion before the year 1723.
An early problem was that there was no means of
precisely measuring the time to detonation reliable fuses did not yet exist, and the burning time of the powder fuse was subject to considerable trial and error. Early powder-burning fuses had to be loaded fuse down to be ignited by firing or a portfire or
slow match
Slow match, also called match cord, is the slow-burning cord or twine fuse
Fuse or FUSE may refer to:
Devices
* Fuse (electrical), a device used in electrical systems to protect against excessive current
** Fuse (automotive), a class of fuses ...
put down the barrel to light the fuse. Other shells were wrapped in
bitumen
Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term a ...
cloth, which would ignite during the firing and in turn ignite a powder fuse. Nevertheless, shells came into regular use in the 16th century, for example, a 1543 English mortar shell was filled with "wildfire."
![Boshin War mortar](https://upload.wikimedia.org/wikipedia/commons/0/00/Boshin_War_mortar.jpg)
By the 18th century, it was known that the fuse toward the muzzle could be lit by the flash through the
windage
Windage is a term used in aerodynamics, firearms ballistics, and automobiles.
Usage
Aerodynamics
Windage is a force created on an object by friction when there is relative movement between air and the object. Windage loss is the reduction in e ...
between the shell and the barrel. At about this time, shells began to be employed for
horizontal fire from
howitzer
A howitzer () is a long- ranged weapon, falling between a cannon (also known as an artillery gun in the United States), which fires shells at flat trajectories, and a mortar, which fires at high angles of ascent and descent. Howitzers, like ot ...
s with a small
propelling charge and, in 1779, experiments demonstrated that they could be used from guns with heavier charges.
The use of exploding shells from field artillery became relatively commonplace from early in the 19th century. Until the mid 19th century, shells remained as simple exploding spheres that used gunpowder, set off by a slow burning fuse. They were usually made of
cast iron
Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
, but
bronze
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids such ...
,
lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cu ...
,
brass
Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other with ...
and even
glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of ...
shell casings were experimented with. The word ''
bomb
A bomb is an explosive weapon that uses the Exothermic process, exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy. Detonations inflict damage principally through ground- and atmosphere-t ...
'' encompassed them at the time, as heard in the lyrics of ''
The Star-Spangled Banner
"The Star-Spangled Banner" is the national anthem of the United States. The lyrics come from the "Defence of Fort M'Henry", a poem written on September 14, 1814, by 35-year-old lawyer and amateur poet Francis Scott Key after witnessing the b ...
'' ("the bombs bursting in air"), although today that sense of ''bomb'' is obsolete. Typically, the thickness of the metal body was about a sixth of their diameter, and they were about two-thirds the weight of solid shot of the same caliber.
To ensure that shells were loaded with their fuses toward the muzzle, they were attached to wooden bottoms called ''
sabots
Sabot may refer to:
* Sabot (firearms), disposable supportive device used in gunpowder ammunitions to fit/patch around a sub-caliber projectile
* Sabot (shoe), a type of wooden shoe
People
* Dick Sabot (1944–2005), American economist and busi ...
''. In 1819, a committee of British artillery officers recognized that they were essential stores and in 1830 Britain standardized sabot thickness as a half-inch. The sabot was also intended to reduce jamming during loading. Despite the use of exploding shells, the use of smoothbore cannons firing spherical projectiles of shot remained the dominant artillery method until the 1850s.
Modern shell
The mid–19th century saw a revolution in artillery, with the introduction of the first practical
rifled breech loading weapons. The new methods resulted in the reshaping of the spherical shell into its modern recognizable cylindro-conoidal form. This shape greatly improved the in-flight stability of the projectile and meant that the primitive time fuzes could be replaced with the percussion fuze situated in the nose of the shell. The new shape also meant that further, armor-piercing designs could be used.
During the 20th century, shells became increasingly streamlined. In World War I, ogives were typically two circular radius head (crh) – the curve was a segment of a circle having a radius of twice the shell caliber. After that war, ogive shapes became more complex and elongated. From the 1960s, higher quality steels were introduced by some countries for their HE shells, this enabled thinner shell walls with less weight of metal and hence a greater weight of explosive. Ogives were further elongated to improve their ballistic performance.
Rifled breech loaders
![Sagahan Armstrong gun used at the Battle of Ueno against the Shogitai 1868](https://upload.wikimedia.org/wikipedia/commons/f/fa/Sagahan_Armstrong_gun_used_at_the_Battle_of_Ueno_against_the_Shogitai_1868.jpg)
Advances in metallurgy in the industrial era allowed for the construction of
rifled breech-loading guns that could fire at a much greater
muzzle velocity
Muzzle velocity is the speed of a projectile (bullet, pellet, slug, ball/shots or shell) with respect to the muzzle at the moment it leaves the end of a gun's barrel (i.e. the muzzle). Firearm muzzle velocities range from approximately to i ...
. After the British artillery was shown up in the
Crimean War
The Crimean War, , was fought from October 1853 to February 1856 between Russia and an ultimately victorious alliance of the Ottoman Empire, France, the United Kingdom and Piedmont-Sardinia.
Geopolitical causes of the war included the de ...
as having barely changed since the
Napoleonic Wars
The Napoleonic Wars (1803–1815) were a series of major global conflicts pitting the French Empire and its allies, led by Napoleon I, against a fluctuating array of European states formed into various coalitions. It produced a period of Fren ...
, the industrialist
William Armstrong was awarded a contract by the government to design a new piece of artillery. Production started in 1855 at the
Elswick Ordnance Company
The Elswick Ordnance Company (sometimes referred to as Elswick Ordnance Works, but usually as "EOC") was a British armaments manufacturing company of the late 19th and early 20th century
History
Originally created in 1859 to separate William A ...
and the
Royal Arsenal
The Royal Arsenal, Woolwich is an establishment on the south bank of the River Thames in Woolwich in south-east London, England, that was used for the manufacture of armaments and ammunition, proofing, and explosives research for the Britis ...
at
Woolwich
Woolwich () is a district in southeast London, England, within the Royal Borough of Greenwich.
The district's location on the River Thames led to its status as an important naval, military and industrial area; a role that was maintained throu ...
.
The piece was
rifled
In firearms, rifling is machining helical grooves into the internal (bore) surface of a gun's barrel for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting to stabilize the proj ...
, which allowed for a much more accurate and powerful action. Although rifling had been tried on small arms since the 15th century, the necessary machinery to accurately rifle artillery only became available in the mid-19th century.
Martin von Wahrendorff
Martin von Wahrendorff (1789 – 1861) was a Swedish diplomat and inventor.
His father Anders von Wahrendorff was the owner of the gun foundry at Åker. Wahrendorff was Grand Master of Ceremonies at the Royal Court of Sweden from 1828 to ...
and
Joseph Whitworth
Sir Joseph Whitworth, 1st Baronet (21 December 1803 – 22 January 1887) was an English engineer, entrepreneur, inventor and philanthropist. In 1841, he devised the British Standard Whitworth system, which created an accepted standard for scr ...
independently produced rifled cannons in the 1840s, but it was Armstrong's gun that was first to see widespread use during the Crimean War. The
cast iron
Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
shell of the Armstrong gun was similar in shape to a
Minié ball
The Minié ball or Minie ball, is a type of hollow-based bullet designed by Claude-Étienne Minié, inventor of the French Minié rifle, for muzzle-loading rifled muskets. It was invented in 1847 and came to prominence in the Crimean War and ...
and had a thin lead coating which made it fractionally larger than the gun's bore and which engaged with the gun's
rifling
In firearms, rifling is machining helical grooves into the internal (bore) surface of a gun's barrel for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting to stabilize the pro ...
grooves to impart spin to the shell. This spin, together with the elimination of
windage
Windage is a term used in aerodynamics, firearms ballistics, and automobiles.
Usage
Aerodynamics
Windage is a force created on an object by friction when there is relative movement between air and the object. Windage loss is the reduction in e ...
as a result of the tight fit, enabled the gun to achieve greater range and accuracy than existing smooth-bore muzzle-loaders with a smaller powder charge.
The gun was also a breech-loader. Although attempts at breech-loading mechanisms had been made since medieval times, the essential engineering problem was that the mechanism couldn't withstand the explosive charge. It was only with the advances in
metallurgy
Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys.
Metallurgy encompasses both the sc ...
and
precision engineering
Precision engineering is a subdiscipline of electrical engineering, software engineering, electronics engineering, mechanical engineering, and optical engineering concerned with designing machines, fixtures, and other structures that have excepti ...
capabilities during the
Industrial Revolution
The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...
that Armstrong was able to construct a viable solution. Another innovative feature was what Armstrong called its "grip", which was essentially a
squeeze bore
A squeeze bore, alternatively taper-bore, cone barrel or conical barrel, is a weapon where the internal gun barrel, barrel diameter progressively decreases towards the muzzle (firearms), muzzle resulting in a reduced final internal diameter. These ...
; the 6 inches of the bore at the muzzle end was of slightly smaller diameter, which centered the shell before it left the barrel and at the same time slightly
swage
Swaging () is a forging process in which the dimensions of an item are altered using dies into which the item is forced. Swaging is usually a cold working process, but also may be hot worked.
The term swage may apply to the process (verb) or ...
d down its lead coating, reducing its diameter and slightly improving its ballistic qualities.
Rifled guns were also developed elsewhere – by Major Giovanni Cavalli and Baron
Martin von Wahrendorff
Martin von Wahrendorff (1789 – 1861) was a Swedish diplomat and inventor.
His father Anders von Wahrendorff was the owner of the gun foundry at Åker. Wahrendorff was Grand Master of Ceremonies at the Royal Court of Sweden from 1828 to ...
in Sweden,
Krupp
The Krupp family (see pronunciation), a prominent 400-year-old German dynasty from Essen, is notable for its production of steel, artillery, ammunition and other armaments. The family business, known as Friedrich Krupp AG (Friedrich Krup ...
in Germany and the
Wiard gun
The Wiard rifle refers to several weapons invented by Norman Wiard, most commonly a semi-steel light artillery piece in six-pounder and twelve-pounder calibers. About 60 were manufactured between 1861 and 1862 during the American Civil War, at ...
in the United States. However, rifled barrels required some means of engaging the shell with the rifling. Lead coated shells were used with the
Armstrong gun
An Armstrong gun was a uniquely designed type of Rifled breech-loader, rifled breech-loading field and heavy gun designed by William George Armstrong, 1st Baron Armstrong, Sir William Armstrong and manufactured in England beginning in 1855 by the ...
, but were not satisfactory so studded projectiles were adopted. However, these did not seal the gap between shell and barrel. Wads at the shell base were also tried without success.
In 1878, the British adopted a copper "
gas-check" at the base of their studded projectiles and in 1879 tried a rotating gas check to replace the studs, leading to the 1881 automatic gas-check. This was soon followed by the Vavaseur copper
driving band Russian 122 mm shrapnel shell, which has been fired, showing rifling marks on the copper driving band around its base and the steel bourrelet nearer the front
A driving band or rotating band is a band of soft metal near the base of an artillery ...
as part of the projectile. The driving band rotated the projectile, centered it in the bore and prevented gas escaping forwards. A driving band has to be soft but tough enough to prevent stripping by rotational and engraving stresses.
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkis ...
is generally most suitable but
cupronickel
Cupronickel or copper-nickel (CuNi) is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. The copper content typically varies from 60 to 90 percent. (Monel is a nickel-copper alloy that contains a minimu ...
or
gilding metal
Gilding metal is a form of brass (an alloy of copper and zinc) with a much higher copper content than zinc content. Exact figures range from 95% copper and 5% zinc to “8 parts copper to 1 of zinc” (11% zinc) in British Army Dress Regulations.
...
were also used.
[Hogg, pp. 165–166.]
Percussion fuze
![No 1 DA Percussion Fuze Mk III Diagram](https://upload.wikimedia.org/wikipedia/commons/4/4d/No_1_DA_Percussion_Fuze_Mk_III_Diagram.jpg)
Although an early percussion fuze appeared in 1650 that used a flint to create sparks to ignite the powder, the shell had to fall in a particular way for this to work and this did not work with spherical projectiles. An additional problem was finding a suitably stable "percussion powder". Progress was not possible until the discovery of
mercury fulminate
Mercury(II) fulminate, or Hg(CNO)2, is a primary explosive. It is highly sensitive to friction, heat and shock and is mainly used as a trigger for other explosives in percussion caps and detonators. Mercury(II) cyanate, though its chemical formula ...
in 1800, leading to priming mixtures for small arms patented by the Rev
Alexander Forsyth
Alexander John Forsyth (28 December 1768 – 11 June 1843) was a Scottish Church of Scotland minister who first successfully used fulminating (or 'detonating') chemicals to prime gunpowder in fire-arms thereby creating what became known as per ...
, and the copper percussion cap in 1818.
The percussion fuze was adopted by Britain in 1842. Many designs were jointly examined by the army and navy, but were unsatisfactory, probably because of the safety and arming features. However, in 1846 the design by Quartermaster Freeburn of the Royal Artillery was adopted by the army. It was a wooden fuze about 6 inches long and used shear wire to hold blocks between the fuze magazine and a burning match. The match was ignited by propellant flash and the shear wire broke on impact. A British naval percussion fuze made of metal did not appear until 1861.
Types of fuzes
*
Percussion fuzes
**
Direct action fuzes
**
Graze fuzes
**
Delay fuzes
**
Base fuzes
*
Airburst fuzes
**
Time fuzes
**
Proximity fuzes
**
Distance measuring fuzes
**
Electronic time fuzes
Smokeless powders
Gunpowder
Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate (saltpeter). ...
was used as the only form of explosive up until the end of the 19th century. Guns using black powder ammunition would have their view obscured by a huge cloud of smoke and concealed shooters were given away by a cloud of smoke over the firing position.
Guncotton
Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and ...
, a nitrocellulose-based material, was discovered by
Swiss
Swiss may refer to:
* the adjectival form of Switzerland
* Swiss people
Places
* Swiss, Missouri
* Swiss, North Carolina
*Swiss, West Virginia
* Swiss, Wisconsin
Other uses
*Swiss-system tournament, in various games and sports
*Swiss Internation ...
chemist
Christian Friedrich Schönbein
Christian Friedrich Schönbein H FRSE(18 October 1799 – 29 August 1868) was a German-Swiss chemist who is best known for inventing the fuel cell (1838) at the same time as William Robert Grove and his discoveries of guncotton and ozone.
Lif ...
in 1846. He promoted its use as a blasting explosive
[Davis, William C., Jr. ''Handloading''. National Rifle Association of America (1981). p. 28.] and sold manufacturing rights to the
Austrian Empire
The Austrian Empire (german: link=no, Kaiserthum Oesterreich, modern spelling , ) was a Central-Eastern European multinational great power from 1804 to 1867, created by proclamation out of the realms of the Habsburgs. During its existence, ...
. Guncotton was more powerful than gunpowder, but at the same time was somewhat more unstable. John Taylor obtained an English patent for guncotton; and John Hall & Sons began
manufacture in Faversham. British interest waned after an explosion destroyed the Faversham factory in 1847. Austrian Baron
Wilhelm Lenk von Wolfsberg
Nikolaus Wilhelm Freiherr Lenk von Wolfsberg (born March 17, 1809, České Budějovice, Budweis, Austrian Empire, Austria; died October 18, 1894, Opava, Troppau, Austrian Empire, Austria) was an Austrian officer (Feldzeugmeister), owner of the Corp ...
built two guncotton plants producing artillery propellant, but it was dangerous under field conditions, and guns that could fire thousands of rounds using gunpowder would reach their service life after only a few hundred shots with the more powerful guncotton.
Small arms could not withstand the pressures generated by guncotton. After one of the Austrian factories blew up in 1862,
Thomas Prentice & Company began manufacturing guncotton in
Stowmarket
Stowmarket ( ) is a market town in Suffolk, England,OS Explorer map 211: Bury St.Edmunds and Stowmarket
Scale: 1:25 000. Publisher:Ordnance Survey – Southampton A2 edition. Publishing Date:2008. on the busy A14 road (Great Britain), A14 trunk ...
in 1863; and British
War Office
The War Office was a department of the British Government responsible for the administration of the British Army between 1857 and 1964, when its functions were transferred to the new Ministry of Defence (MoD). This article contains text from ...
chemist Sir
Frederick Abel
Sir Frederick Augustus Abel, 1st Baronet (17 July 18276 September 1902) was an English chemist who was recognised as the leading British authority on explosives. He is best known for the invention of cordite as a replacement for gunpowder in f ...
began thorough research at
Waltham Abbey Royal Gunpowder Mills
The Royal Gunpowder Mills are a former industrial site in Waltham Abbey, England.
It was one of three Royal Gunpowder Mills in the United Kingdom (the others being at Ballincollig and Faversham). Waltham Abbey is the only site to have survive ...
leading to a manufacturing process that eliminated the impurities in nitrocellulose making it safer to produce and a stable product safer to handle. Abel patented this process in 1865, when the second Austrian guncotton factory exploded. After the Stowmarket factory exploded in 1871, Waltham Abbey began production of guncotton for torpedo and mine warheads.
[Sharpe, Philip B. ''Complete Guide to Handloading''. 3rd edition (1953). Funk & Wagnalls. pp. 141–144.]
![Heike Kamerlingh Onnes - 33 - James Dewar in the Royal Institution in London, around 1900](https://upload.wikimedia.org/wikipedia/commons/c/c5/Heike_Kamerlingh_Onnes_-_33_-_James_Dewar_in_the_Royal_Institution_in_London%2C_around_1900.png)
In 1884,
Paul Vieille
Paul may refer to:
*Paul (given name), a given name (includes a list of people with that name)
* Paul (surname), a list of people
People
Christianity
*Paul the Apostle (AD c.5–c.64/65), also known as Saul of Tarsus or Saint Paul, early Chri ...
invented a smokeless powder called
Poudre B (short for ''poudre blanche''—white powder, as distinguished from
black powder
Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, carbon (in the form of charcoal) and potassium nitrate (saltpeter). Th ...
)
[Davis, Tenney L. ''The Chemistry of Powder & Explosives'' (1943), pages 289–292.] made from 68.2% insoluble
nitrocellulose
Nitrocellulose (also known as cellulose nitrate, flash paper, flash cotton, guncotton, pyroxylin and flash string, depending on form) is a highly flammable compound formed by nitrating cellulose through exposure to a mixture of nitric acid and ...
, 29.8% soluble nitrocellusose gelatinized with
ether
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...
and 2% paraffin. This was adopted for the Lebel rifle.
[Hogg, Oliver F. G. ''Artillery: Its Origin, Heyday and Decline'' (1969), p. 139.] Vieille's powder revolutionized the effectiveness of small guns, because it gave off almost no smoke and was three times more powerful than black powder. Higher
muzzle velocity
Muzzle velocity is the speed of a projectile (bullet, pellet, slug, ball/shots or shell) with respect to the muzzle at the moment it leaves the end of a gun's barrel (i.e. the muzzle). Firearm muzzle velocities range from approximately to i ...
meant a flatter
trajectory
A trajectory or flight path is the path that an object with mass in motion follows through space as a function of time. In classical mechanics, a trajectory is defined by Hamiltonian mechanics via canonical coordinates; hence, a complete traj ...
and less wind drift and bullet drop, making 1000 meter shots practicable. Other European countries swiftly followed and started using their own versions of Poudre B, the first being
Germany
Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...
and
Austria
Austria, , bar, Östareich officially the Republic of Austria, is a country in the southern part of Central Europe, lying in the Eastern Alps. It is a federation of nine states, one of which is the capital, Vienna, the most populous ...
which introduced new weapons in 1888. Subsequently, Poudre B was modified several times with various compounds being added and removed.
Krupp
The Krupp family (see pronunciation), a prominent 400-year-old German dynasty from Essen, is notable for its production of steel, artillery, ammunition and other armaments. The family business, known as Friedrich Krupp AG (Friedrich Krup ...
began adding
diphenylamine
Diphenylamine is an organic compound with the formula (C6H5)2NH. The compound is a derivative of aniline, consisting of an amine bound to two phenyl groups. The compound is a colorless solid, but commercial samples are often yellow due to oxidized ...
as a stabilizer in 1888.
Britain conducted trials on all the various types of propellant brought to their attention, but were dissatisfied with them all and sought something superior to all existing types. In 1889, Sir
Frederick Abel
Sir Frederick Augustus Abel, 1st Baronet (17 July 18276 September 1902) was an English chemist who was recognised as the leading British authority on explosives. He is best known for the invention of cordite as a replacement for gunpowder in f ...
,
James Dewar
Sir James Dewar (20 September 1842 – 27 March 1923) was a British chemist and physicist. He is best known for his invention of the vacuum flask, which he used in conjunction with research into the liquefaction of gases. He also studied ato ...
and Dr. W. Kellner patented (No. 5614 and No. 11,664 in the names of Abel and Dewar) a new formulation that was manufactured at the Royal Gunpowder Factory at Waltham Abbey. It entered British service in 1891 as
Cordite
Cordite is a family of smokeless propellants developed and produced in the United Kingdom since 1889 to replace black powder as a military propellant. Like modern gunpowder, cordite is classified as a low explosive because of its slow burni ...
Mark 1. Its main composition was 58% nitro-glycerine, 37% guncotton and 3% mineral jelly. A modified version, Cordite MD, entered service in 1901, this increased guncotton to 65% and reduced nitro-glycerine to 30%, this change reduced the combustion temperature and hence erosion and barrel wear. Cordite could be made to burn more slowly which reduced maximum pressure in the chamber (hence lighter breeches, etc.), but longer high pressure – significant improvements over gunpowder. Cordite could be made in any desired shape or size.
[Hogg, Oliver F. G. ''Artillery: Its Origin, Heyday and Decline'' (1969), p. 141.] The creation of cordite led to a lengthy court battle between Nobel, Maxim, and another inventor over alleged British
patent
A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A p ...
infringement.
Other shell types
![Carcass shell](https://upload.wikimedia.org/wikipedia/commons/f/fb/Carcass_shell.jpg)
A variety of fillings have been used in shells throughout history. An incendiary shell was invented by Valturio in 1460. The
carcass shell
Carcass or Carcase (both pronounced ) may refer to:
*Dressed carcass, the body of a livestock animal ready for butchery, after removal of skin, visceral organs, head, feet etc.
*Carrion, the decaying dead body of an animal or human being
*The str ...
was first used by the French under
Louis XIV
, house = Bourbon
, father = Louis XIII
, mother = Anne of Austria
, birth_date =
, birth_place = Château de Saint-Germain-en-Laye, Saint-Germain-en-Laye, France
, death_date =
, death_place = Palace of Versa ...
in 1672. Initially in the shape of an
oblong
An oblong is a non-square rectangle.
Oblong may also refer to:
Places
* Oblong, Illinois, a village in the United States
* Oblong Township, Crawford County, Illinois, United States
* A strip of land on the New York-Connecticut border in the Unit ...
in an iron frame (with poor ballistic properties) it evolved into a spherical shell. Their use continued well into the 19th century.
A modern version of the incendiary shell was developed in 1857 by the British and was known as ''Martin's shell'' after its inventor. The shell was filled with molten iron and was intended to break up on impact with an enemy ship, splashing molten iron on the target. It was used by the Royal Navy between 1860 and 1869, replacing
heated shot
Heated shot or hot shot is round shot that is heated before firing from muzzle-loading cannons, for the purpose of setting fire to enemy warships, buildings, or equipment. The use of heated shot dates back centuries; it was a powerful weapon agains ...
as an anti-ship, incendiary projectile.
Two patterns of incendiary shell were used by the British in World War I, one designed for use against Zeppelins.
Similar to incendiary shells were star shells, designed for illumination rather than arson. Sometimes called lightballs they were in use from the 17th century onwards. The British adopted parachute lightballs in 1866 for 10-, 8- and 5-inch calibers. The 10-inch wasn't officially declared obsolete until 1920.
[Hogg, pp. 174–176.]
Smoke balls also date back to the 17th century, British ones contained a mix of saltpetre, coal, pitch, tar, resin, sawdust, crude antimony and sulphur. They produced a "noisome smoke in abundance that is impossible to bear". In 19th-century British service, they were made of concentric paper with a thickness about 1/15th of the total diameter and filled with powder, saltpeter, pitch, coal and tallow. They were used to 'suffocate or expel the enemy in casemates, mines or between decks; for concealing operations; and as signals.
During the
First World War
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
,
shrapnel shell
Shrapnel shells were anti-personnel artillery munitions which carried many individual bullets close to a target area and then ejected them to allow them to continue along the shell's trajectory and strike targets individually. They relied almo ...
s and explosive shells inflicted terrible casualties on infantry, accounting for nearly 70% of all war casualties and leading to the adoption of steel
combat helmet
A combat helmet or battle helmet is a type of helmet. It is a piece of personal armor designed specifically to protect the head during combat. Modern combat helmets are mainly designed to protect from shrapnel and fragments, offer some protec ...
s on both sides. Frequent problems with shells led to many military disasters with
dud shells, most notably during the 1916
Battle of the Somme
The Battle of the Somme ( French: Bataille de la Somme), also known as the Somme offensive, was a battle of the First World War fought by the armies of the British Empire and French Third Republic against the German Empire. It took place bet ...
. Shells filled with poison
gas
Gas is one of the four fundamental states of matter (the others being solid, liquid, and plasma).
A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or ...
were used from 1917 onwards.
Propulsion
Artillery shells are differentiated by how the shell is loaded and propelled, and the type of breech mechanism.
Fixed ammunition
Fixed ammunition has three main components: the
fuze
In military munitions, a fuze (sometimes fuse) is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze d ...
d projectile, the
casing to hold the propellants and
primer
Primer may refer to:
Arts, entertainment, and media Films
* ''Primer'' (film), a 2004 feature film written and directed by Shane Carruth
* ''Primer'' (video), a documentary about the funk band Living Colour
Literature
* Primer (textbook), a t ...
, and the single propellant charge. Everything is included in a ready-to-use package and in British ordnance terms is called
fixed quick firing. Often guns which use fixed ammunition use
sliding-block or sliding-wedge breeches and the case provides
obturation
In the field of firearms and airguns, obturation denotes necessary barrel blockage or fit by a deformed soft projectile (obturation in general is closing up an opening). A bullet or pellet, made of soft material and often with a concave base, wi ...
which seals the
breech
Breech may refer to:
* Breech (firearms), the opening at the rear of a gun barrel where the cartridge is inserted in a breech-loading weapon
* breech, the lower part of a pulley block
* breech, the penetration of a boiler where exhaust gases leav ...
of the gun and prevents propellant gasses from escaping. Sliding block breeches can be horizontal or vertical. Advantages of fixed ammunition are simplicity, safety, moisture resistance and speed of loading. Disadvantages are eventually a fixed round becomes too long or too heavy to load by a gun crew. Another issue is the inability to vary propellant charges to achieve different velocities and ranges. Lastly, there is the issue of resource usage since a fixed round uses a case, which can be an issue in a prolonged war if there are metal shortages.
Separate loading cased charge
Separate loading cased charge ammunition has three main components: the fuzed projectile, the casing to hold the propellants and primer, and the bagged propellant charges. The components are usually separated into two or more parts. In British ordnance terms, this type of ammunition is called
separate quick firing. Often guns which use separate loading cased charge ammunition use sliding-block or sliding-wedge breeches and during
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
and
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
Germany predominantly used fixed or separate loading cased charges and sliding block breeches even for their largest guns. A variant of separate loading cased charge ammunition is semi-fixed ammunition. With semi-fixed ammunition the round comes as a complete package but the projectile and its case can be separated. The case holds a set number of bagged charges and the gun crew can add or subtract propellant to change range and velocity. The round is then reassembled, loaded, and fired. Advantages include easier handling for larger caliber rounds, while range and velocity can easily be varied by increasing or decreasing the number of propellant charges. Disadvantages include more complexity, slower loading, less safety, less moisture resistance, and the metal cases can still be a material resource issue.
Separate loading bagged charge
Separate loading bagged charge ammunition there are three main components: the fuzed projectile, the bagged charges and the primer. Like separate loading cased charge ammunition, the number of propellant charges can be varied. However, this style of ammunition does not use a cartridge case and it achieves obturation through a
screw breech instead of a sliding block. Sometimes when reading about artillery the term separate loading ammunition will be used without clarification of whether a cartridge case is used or not, in which case refer to the type of breech used. Heavy artillery pieces and
naval artillery
Naval artillery is artillery mounted on a warship, originally used only for naval warfare and then subsequently used for naval gunfire support, shore bombardment and anti-aircraft roles. The term generally refers to tube-launched projectile-firi ...
tend to use bagged charges and projectiles because the weight and size of the projectiles and propelling charges can be more than a gun crew can manage. Advantages include easier handling for large rounds, decreased metal usage, while range and velocity can be varied by using more or fewer propellant charges. Disadvantages include more complexity, slower loading, less safety and less moisture resistance.
Range-enhancing technologies
![XM1113 in flight](https://upload.wikimedia.org/wikipedia/commons/8/89/XM1113_in_flight.jpg)
Extended-range shells are sometimes used. These special shell designs may be
rocket-assisted projectile
A rocket-assisted projectile (RAP) is a cannon, howitzer, Mortar (weapon), mortar, or recoilless rifle round incorporating a rocket motor for independent propulsion. This gives the projectile greater speed and range than a non-assisted Ballistics, ...
s (RAP) or
base bleed
Base bleed is a system used on some artillery shells to increase range, typically by about 20–35%. It expels gas into the low pressure area behind the shell to reduce base drag (it does not produce thrust).
Since base bleed extends the ran ...
(BB) to increase range. The first has a small rocket motor built into its base to provide additional thrust. The second has a pyrotechnic device in its base that bleeds gas to fill the partial vacuum created behind the shell and hence reduce base-drag. These shell designs usually have reduced high-explosive filling to remain within the permitted mass for the projectile, and hence less lethality.
Sizes
![British crew preparing 155 mm shells Italy 22-02-1945 IWM NA 22473](https://upload.wikimedia.org/wikipedia/commons/6/67/British_crew_preparing_155_mm_shells_Italy_22-02-1945_IWM_NA_22473.jpg)
The
caliber
In guns, particularly firearms, caliber (or calibre; sometimes abbreviated as "cal") is the specified nominal internal diameter of the gun barrel Gauge (firearms) , bore – regardless of how or where the bore is measured and whether the f ...
of a shell is its
diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid for ...
. Depending on the historical period and national preferences, this may be specified in
millimeter
330px, Different lengths as in respect to the electromagnetic spectrum, measured by the metre and its derived scales. The microwave is between 1 meter to 1 millimeter.
The millimetre (American and British English spelling differences#-re, -er, ...
s,
centimeter
330px, Different lengths as in respect to the Electromagnetic spectrum, measured by the Metre and its deriveds scales. The Microwave are in-between 1 meter to 1 millimeter.
A centimetre (international spelling) or centimeter (American spellin ...
s, or
inch
Measuring tape with inches
The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to yard or of a foot. Derived from the Roman uncia ("twelfth") ...
es. The length of gun barrels for large
cartridges and shells (naval) is frequently quoted in terms of the ratio of the barrel length to the bore size, also called
caliber
In guns, particularly firearms, caliber (or calibre; sometimes abbreviated as "cal") is the specified nominal internal diameter of the gun barrel Gauge (firearms) , bore – regardless of how or where the bore is measured and whether the f ...
. For example, the
16"/50 caliber Mark 7 gun
The 16"/50 caliber Mark 7 – United States Naval Gun is the main armament of the ''Iowa''-class battleships and was the planned main armament of the cancelled .
Description
Due to a lack of communication during design, the Bureau of Ordnance ...
is 50 calibers long, that is, 16"×50=800"=66.7 feet long. Some guns, mainly British, were specified by the weight of their shells (see below).
Explosive rounds as small as
12.7 x 82 mm and
13 x 64 mm have been used on aircraft and armored vehicles, but their small explosive yield have led some nations to limit their explosive rounds to
20mm
20 mm caliber is a specific size of popular autocannon ammunition. It is typically used to distinguish smaller-caliber weapons, commonly called "guns", from larger-caliber "cannons" (e.g. machine gun vs. autocannon). All 20 mm cartridges ha ...
(.78 in) or larger. International Law precludes the use of explosive ammunition for use against individual persons, but not against vehicles and aircraft. The largest shells ever fired during war were those from the German super-
railway gun
A railway gun, also called a railroad gun, is a large artillery piece, often surplus naval artillery, mounted on, transported by, and fired from a specially designed railroad car, railway wagon. Many countries have built railway guns, but the ...
s,
Gustav and Dora, which were 800 mm (31.5 in) in caliber. Very large shells have been replaced by
rocket
A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely fr ...
s,
missiles
In military terminology, a missile is a guided airborne ranged weapon capable of self-propelled flight usually by a jet engine or rocket motor. Missiles are thus also called guided missiles or guided rockets (when a previously unguided rocket i ...
, and
bomb
A bomb is an explosive weapon that uses the Exothermic process, exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy. Detonations inflict damage principally through ground- and atmosphere-t ...
s. Today the largest shells in common use are
155 mm
155 mm (6.1 in) is a common, NATO-standard, artillery caliber. It is defined in AOP-29 part 1 with reference to STANAG 4425. It is commonly used in field guns, howitzers, and gun-howitzers.
Land warfare
The caliber originated in France after ...
(6.1 in).
![US Army WWII field artillery](https://upload.wikimedia.org/wikipedia/commons/5/59/US_Army_WWII_field_artillery.jpg)
Gun calibers have standardized around a few common sizes, especially in the larger range, mainly due to the uniformity required for efficient military logistics. Artillery shells of 105 and 155 mm for artillery with 105 and 120 mm for
tank gun
A tank gun is the main armament of a tank. Modern tank guns are high-velocity, large-caliber artilleries capable of firing kinetic energy penetrators, high-explosive anti-tank, and cannon-launched guided projectiles. Anti-aircraft guns can also ...
s are common in
NATO
The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...
allied countries. Artillery shells of 122, 130, and 152 mm with tank gun ammunition of 100, 115, and 125 mm calibers remain in common usage among the regions of Eastern Europe, Western Asia, Northern Africa, and Eastern Asia. Most common calibers have been in use for many decades, since it is
logistically complex to change the caliber of all guns and ammunition stores.
The weight of shells increases by and large with caliber. A typical 155 mm (6.1 in) shell weighs about 50 kg (110 lbs), a common 203 mm (8 in) shell about 100 kg (220 lbs), a concrete demolition 203 mm (8 in) shell 146 kg (322 lbs), a 280 mm (11 in) battleship shell about 300 kg (661 lbs), and a 460 mm (18 in) battleship shell over 1,500 kg (3,307 lbs). The
Schwerer Gustav
Schwerer Gustav (English: ''Heavy Gustav'') was a German railway gun. It was developed in the late 1930s by Krupp in Rügenwalde as siege artillery for the explicit purpose of destroying the main forts of the French Maginot Line, the strongest ...
large-calibre gun fired shells that weighed between 4,800 kg (10,582 lbs) and 7,100 kg (15,653 lbs).
During the 19th century, the British adopted a particular form of designating artillery. Field guns were designated by nominal standard projectile weight, while howitzers were designated by barrel caliber. British guns and their ammunition were designated in
pounds, e.g., as "two-pounder" shortened to "2-pr" or "2-pdr". Usually, this referred to the actual weight of the standard projectile (shot, shrapnel, or high explosive), but, confusingly, this was not always the case.
Some were named after the weights of obsolete projectile types of the same caliber, or even obsolete types that were considered to have been functionally equivalent. Also, projectiles fired from the same gun, but of non-standard weight, took their name from the gun. Thus, conversion from "pounds" to an actual barrel diameter requires consulting a historical reference. A mixture of designations were in use for land artillery from the First World War (such as the
BL 60-pounder gun
The Ordnance BL 60-pounder was a British 5 inch (127 mm) heavy field gun designed in 1903–05 to provide a new capability that had been partially met by the interim QF 4.7 inch Gun Mk I - IV, QF 4.7 inch Gun. It was designed for both ...
,
RML 2.5 inch Mountain Gun
The Ordnance RML 2.5-inch mountain gun was a British rifled muzzle-loading mountain gun of the late 19th century designed to be broken down into four loads for carrying by man or mule. It was primarily used by the Indian Army.
History
It was ...
, 4 inch gun, 4.5 inch howitzer) through to the end of World War II (5.5 inch medium gun,
25-pounder gun-howitzer, 17-pounder tank gun), but the majority of naval guns were by caliber. After the end of World War II, field guns were designated by caliber.
Types
![BL 12 inch Palliser shot Mk II diagram](https://upload.wikimedia.org/wikipedia/commons/7/71/BL_12_inch_Palliser_shot_Mk_II_diagram.jpg)
There are many different types of shells. The principal ones include:
Armor-piercing shells
With the introduction of the first
ironclad
An ironclad is a steam engine, steam-propelled warship protected by Wrought iron, iron or steel iron armor, armor plates, constructed from 1859 to the early 1890s. The ironclad was developed as a result of the vulnerability of wooden warships ...
s in the 1850s and 1860s, it became clear that shells had to be designed to effectively pierce the ship armor. A series of British tests in 1863 demonstrated that the way forward lay with high-velocity lighter shells. The first
pointed armor-piercing shell was introduced by Major Palliser in 1863. Approved in 1867,
Palliser shot and shell
upPalliser shot, Mark I, for 9-inch Rifled Muzzle Loading (RML) gun
Palliser shot is an early British armour-piercing artillery projectile, intended to pierce the armour protection of warships being developed in the second half of the 19th centur ...
was an improvement over the ordinary elongated shot of the time. Palliser shot was made of
cast iron
Cast iron is a class of iron–carbon alloys with a carbon content more than 2%. Its usefulness derives from its relatively low melting temperature. The alloy constituents affect its color when fractured: white cast iron has carbide impuriti ...
, the head being chilled in casting to harden it, using composite molds with a metal, water cooled portion for the head.
Britain also deployed Palliser shells in the 1870s–1880s. In the shell, the cavity was slightly larger than in the shot and was filled with 1.5% gunpowder instead of being empty, to provide a small explosive effect after penetrating armor plating. The shell was correspondingly slightly longer than the shot to compensate for the lighter cavity. The powder filling was ignited by the shock of impact and hence did not require a fuze.
["]Treatise on Ammunition
''Treatise on Ammunition'', from 1926 retitled ''Text Book of Ammunition'', is a series of manuals detailing all British Empire military and naval service ammunition and associated equipment in use at the date of publication. It was published by ...
", 4th Edition 1887, pp. 203–205. However, ship armor rapidly improved during the 1880s and 1890s, and it was realised that explosive shells with
steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
had advantages including better fragmentation and resistance to the stresses of firing. These were cast and forged steel.
AP shells containing an explosive filling were initially distinguished from their non-HE counterparts by being called a "shell" as opposed to "shot". By the time of the Second World War, AP shells with a
bursting charge
In fireworks, a burst charge (usually black powder) is a pyrotechnic mixture placed in a shell which is ignited when the shell reaches the desired height in order to create an explosion and spread the stars. Burst charge compositions are usually ...
were sometimes distinguished by appending the suffix "HE". At the beginning of the war, APHE was common in
anti-tank
Anti-tank warfare originated from the need to develop technology and tactics to destroy tanks during World War I. Since the Triple Entente deployed the first tanks in 1916, the German Empire developed the first anti-tank weapons. The first deve ...
shells of 75 mm caliber and larger due to the similarity with the much larger naval armor piercing shells already in common use. As the war progressed, ordnance design evolved so that the bursting charges in APHE became ever smaller to non-existent, especially in smaller caliber shells, e.g.
Panzergranate 39
The Panzergranate 39 or Pzgr. 39 was a German armor-piercing shell used during World War II. It was manufactured in various calibers and was the most common anti-tank shell used in German tank gun, tank (German: ''Kampfwagenkanone''; shorted to ' ...
with only 0.2% HE filling.
Types of armor-piercing ammunition
*
Armor-piercing
Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour.
From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many warsh ...
– a solid shot
**
Armor-piercing ballistic capped (APBC)
**
Armor-piercing capped (APC)
**
Armor-piercing capped ballistic capped (APCBC)
**
Armor-piercing composite rigid (APCR), also known as High-Velocity Armor-Piercing (HVAP)
**
Armor-piercing composite non-rigid
Armour-piercing ammunition (AP) is a type of projectile designed to penetrate either body armour or vehicle armour.
From the 1860s to 1950s, a major application of armour-piercing projectiles was to defeat the thick armour carried on many warsh ...
(APCRNR)
**
Armor-piercing discarding sabot
Armour-piercing discarding sabot (APDS) is a type of spin-stabilized kinetic energy projectile for anti-armour warfare. Each projectile consists of a sub-calibre round fitted with a sabot. The combination of a lighter sub-calibre projectile wi ...
(APDS)
**
Armor-piercing fin-stabilized discarding sabot
Armour-piercing fin-stabilized discarding sabot (APFSDS), long dart penetrator, or simply dart ammunition, is a type of kinetic energy penetrator ammunition used to attack modern vehicle armour. As an armament for main battle tanks, it succeeds A ...
(APFSDS)
*
Armor piercing high-explosive – a mostly solid shell with an explosive element fused to detonate after the shell has penetrated the armour protection
**
Armor-piercing high explosive tracer (APHE-T)
**
Semi-armor piercing high-explosive (SAPHE)
**
Semi-armor piercing high-explosive incendiary (SAPHEI)
**
Semi-armor piercing high-explosive incendiary tracer (SAPHEI-T)
* Non-kinetic-energy shells – uses chemical energy (explosion) to go through armor
**
High-explosive anti-tank
High-explosive anti-tank (HEAT) is the effect of a shaped charge explosive that uses the Munroe effect to penetrate heavy armor. The warhead functions by having an explosive charge collapse a metal liner inside the warhead into a high-velocity ...
(HEAT)
**
High-explosive squash head
High explosive squash head (HESH) in British terminology, or high explosive plastic/plasticized (HEP) in American terminology, is a type of explosive projectile which uses a plastic explosive that conforms to the surface of a target before detonat ...
(HESH), also known as High-explosive Plastic (HEP)
High-explosive shells
![75mm melanite shell section for instruction](https://upload.wikimedia.org/wikipedia/commons/5/5b/75mm_melanite_shell_section_for_instruction.jpg)
Although smokeless powders were used as a propellant, they could not be used as the substance for the explosive warhead, because shock sensitivity sometimes caused
detonation
Detonation () is a type of combustion involving a supersonic exothermic front accelerating through a medium that eventually drives a shock front propagating directly in front of it. Detonations propagate supersonically through shock waves with ...
in the artillery barrel at the time of firing.
Picric acid
Picric acid is an organic compound with the formula (O2N)3C6H2OH. Its IUPAC name is 2,4,6-trinitrophenol (TNP). The name "picric" comes from el, πικρός (''pikros''), meaning "bitter", due to its bitter taste. It is one of the most acidic ...
was the first high-explosive nitrated
organic compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...
widely considered suitable to withstand the shock of firing in conventional
artillery
Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...
. In 1885, based on research of Hermann Sprengel, French chemist
Eugène Turpin
François Eugène Turpin (30 September 1848 – 24 January 1927) was a French chemist involved in research of explosive materials. He lived in Colombes.
Biography
In 1881 Turpin proposed panclastites, a class of Sprengel explosives based on a mi ...
patented the use of pressed and cast picric acid in
blasting charges and
artillery shell
A shell, in a military context, is a projectile whose payload contains an explosive, incendiary, or other chemical filling. Originally it was called a bombshell, but "shell" has come to be unambiguous in a military context. Modern usage ...
s. In 1887, the French government adopted a mixture of picric acid and guncotton under the name ''Melinite''. In 1888, Britain started manufacturing a very similar mixture in
Lydd
Lydd is a town and electoral ward in Kent, England, lying on Romney Marsh. It is one of the larger settlements on the marsh, and the most southerly town in Kent. Lydd reached the height of its prosperity during the 13th century, when it was a co ...
, Kent, under the name ''Lyddite''.
Japan followed with an "improved" formula known as ''
shimose powder was a type of explosive shell-filling developed by the Japanese naval engineer (1860–1911).
Shimose, born in Hiroshima Prefecture, graduated from Tokyo Imperial University and became one of Japan's earliest holders of a doctorate in engin ...
''. In 1889, a similar material, a mixture of ammonium cresylate with trinitrocresol, or an ammonium salt of trinitrocresol, started to be manufactured under the name ''
ecrasite Ecrasite is an explosive material which is unaffected by moisture, shock or fire. It is a mixture of ammonium salts of cresol, phenol and various nitrocresols and nitrophenols principally trinitrocresol and picric acid. It was invented in 1888-188 ...
'' in
Austria-Hungary
Austria-Hungary, often referred to as the Austro-Hungarian Empire,, the Dual Monarchy, or Austria, was a constitutional monarchy and great power in Central Europe between 1867 and 1918. It was formed with the Austro-Hungarian Compromise of ...
. By 1894, Russia was manufacturing artillery shells filled with picric acid. Ammonium picrate (known as ''Dunnite'' or
explosive D
Dunnite, also known as Explosive D or systematically as ammonium picrate, is an explosive developed in 1906 by US Army Major Beverly W. Dunn, who later served as the chief inspector of the Bureau of Transportation Explosives. Ammonium picrate is ...
) was used by the United States beginning in 1906.
[Brown, G. I. (1998) ''The Big Bang: a History of Explosives''. Sutton Publishing. . pp. 151–163.] Germany began filling artillery shells with
TNT
Trinitrotoluene (), more commonly known as TNT, more specifically 2,4,6-trinitrotoluene, and by its preferred IUPAC name 2-methyl-1,3,5-trinitrobenzene, is a chemical compound with the formula C6H2(NO2)3CH3. TNT is occasionally used as a reagen ...
in 1902.
Toluene
Toluene (), also known as toluol (), is a substituted aromatic hydrocarbon. It is a colorless, water-insoluble liquid with the smell associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) at ...
was less readily available than phenol, and TNT is less powerful than picric acid, but the improved safety of munitions manufacturing and storage caused the replacement of picric acid by TNT for most military purposes between the World Wars.
However, pure TNT was expensive to produce and most nations made some use of mixtures using cruder TNT and ammonium nitrate, some with other compounds included. These fills included Ammonal, Schneiderite and
Amatol
Amatol is a highly explosive material made from a mixture of TNT and ammonium nitrate. The British name originates from the words ammonium and toluene (the precursor of TNT). Similar mixtures (one part dinitronaphthalene and seven parts ammoniu ...
. The latter was still in wide use in
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
.
The percentage of shell weight taken up by its explosive fill increased steadily throughout the 20th Century. Less than 10% was usual in the first few decades; by
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
, leading designs were around 15%. However, British researchers in that war identified 25% as being the optimal design for
anti-personnel
An anti-personnel weapon is a weapon primarily used to maim or kill infantry and other personnel not behind armor, as opposed to attacking structures or vehicles, or hunting game. The development of defensive fortification and combat vehicles ga ...
purposes, based on the recognition that far smaller fragments than hitherto would give a better effect. This guideline was achieved by the 1960s with the 155 mm L15 shell, developed as part of the German-British
FH-70
The FH70 (field howitzer for the 1970s) is a towed howitzer in use with several nations.
History
In 1963, NATO agreed a NATO Basic Military Requirement 39 for close support artillery, either towed or tracked. Subsequently, Germany and UK sta ...
program. The key requirement for increasing the HE content without increasing shell weight was to reduce the thickness of shell walls, which required improvements in high tensile steel.
![15in howitzer Menin Rd 5 October 1917](https://upload.wikimedia.org/wikipedia/commons/b/b9/15in_howitzer_Menin_Rd_5_October_1917.jpg)
The most common shell type is
high explosive
An explosive (or explosive material) is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An exp ...
, commonly referred to simply as HE. They have a strong
steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...
case, a bursting charge, and a
fuse
Fuse or FUSE may refer to:
Devices
* Fuse (electrical), a device used in electrical systems to protect against excessive current
** Fuse (automotive), a class of fuses for vehicles
* Fuse (hydraulic), a device used in hydraulic systems to protect ...
. The fuse detonates the bursting charge which shatters the case and scatters hot, sharp case pieces (''fragments'', ''splinters'') at high velocity. Most of the damage to soft targets, such as unprotected personnel, is caused by shell pieces rather than by the blast. The term "shrapnel" is sometimes used to describe the shell pieces, but
shrapnel shell
Shrapnel shells were anti-personnel artillery munitions which carried many individual bullets close to a target area and then ejected them to allow them to continue along the shell's trajectory and strike targets individually. They relied almo ...
s functioned very differently and are long obsolete. The speed of fragments is limited by
Gurney equations
The Gurney equations are a set of mathematical formulas used in explosives engineering to relate how fast an explosive will accelerate an adjacent layer of metal or other material when the explosive detonates. This determines how fast fragments a ...
. Depending on the type of
fuse
Fuse or FUSE may refer to:
Devices
* Fuse (electrical), a device used in electrical systems to protect against excessive current
** Fuse (automotive), a class of fuses for vehicles
* Fuse (hydraulic), a device used in hydraulic systems to protect ...
used the HE shell can be set to burst on the ground (percussion), in the air above the ground, which is called air burst (time or
proximity
Proximity may refer to:
* Distance, a numerical description of how far apart objects are
* Proxemics, the study of human spatial requirements and the effects of population density
* Proximity (2000 film), ''Proximity'' (2000 film), an action/thril ...
), or after penetrating a short distance into the ground (percussion with delay, either to transmit more ground shock to covered positions, or to reduce the spread of fragments). Projectiles with enhanced fragmentation are called high-explosive fragmentation (HE-FRAG).
RDX
RDX (abbreviation of "Research Department eXplosive") or hexogen, among other names, is an organic compound with the formula (O2N2CH2)3. It is a white solid without smell or taste, widely used as an explosive. Chemically, it is classified as a n ...
and TNT mixtures are the standard chemicals used, notably
Composition B
Composition B, colloquially Comp B, is an explosive consisting of castable mixtures of RDX and TNT. It is used as the main explosive filling in artillery projectiles, rockets, land mines, hand grenades and various other munitions. It was also use ...
and
Cyclotol Cyclotol is an explosive consisting of castable mixtures of RDX and TNT. It is related to the more common Composition B, which is roughly 60% RDX and 40% TNT; various compositions of Cyclotol contain from 65% to 80% RDX.
Typical ranges are from 60/ ...
. The introduction of "insensitive munition" requirements, agreements and regulations in the 1990s caused modern western designs to use various types of plastic bonded explosives (PBX) based on RDX.
Common
Common shells designated in the early (i.e. 1800s) British explosive shells were filled with "low explosives" such as "P mixture" (gunpowder) and usually with a fuze in the nose. Common shells on bursting (non-detonating) tended to break into relatively large fragments which continued along the shell's trajectory rather than laterally. They had some incendiary effect.
In the late 19th century "double common shells" were developed, lengthened so as to approach twice the standard shell weight, to carry more powder and hence increase explosive effect. They suffered from instability in flight and low velocity and were not widely used.
In 1914, common shells with a diameter of 6-inches and larger were of cast steel, while smaller diameter shells were of forged steel for service and cast iron for practice. They were replaced by "common lyddite" shells in the late 1890s but some stocks remained as late as 1914. In British service common shells were typically painted black with a red band behind the nose to indicate the shell was filled.
Common pointed
Common pointed shells, or CP were a type of common shell used in naval service from the 1890s – 1910s which had a solid nose and a percussion fuze in the base rather than the common shell's nose fuze. The ogival two C.R.H. solid pointed nose was considered suitable for attacking shipping but was not armor-piercing – the main function was still explosive. They were of cast or forged (three- and six-pounder) steel and contained a gunpowder bursting charge slightly smaller than that of a common shell, a trade off for the longer heavier nose.
In British service common pointed shells were typically painted black, except 12-pounder shells specific for QF guns which were painted lead colour to distinguish them from 12-pounder shells usable with both BL and QF guns. A red ring behind the nose indicated the shell was filled.
By World War II they were superseded in Royal Navy service by common pointed capped (CPC) and semi-armor piercing (
SAP
Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant.
Sap is distinct from latex, resin, or cell sap; it is a separa ...
), filled with TNT.
Common lyddite
Common lyddite shells were British explosive shells filled with
Lyddite
Picric acid is an organic compound with the formula (O2N)3C6H2OH. Its IUPAC name is 2,4,6-trinitrophenol (TNP). The name "picric" comes from el, πικρός (''pikros''), meaning "bitter", due to its bitter taste. It is one of the most acidic ...
were initially designated "common lyddite" and beginning in 1896 were the first British generation of modern "high explosive" shells. Lyddite is
picric acid
Picric acid is an organic compound with the formula (O2N)3C6H2OH. Its IUPAC name is 2,4,6-trinitrophenol (TNP). The name "picric" comes from el, πικρός (''pikros''), meaning "bitter", due to its bitter taste. It is one of the most acidic ...
fused at and allowed to solidify, producing a much denser dark-yellow form which is not affected by moisture and is easier to detonate than the liquid form. Its French equivalent was "melinite", Japanese equivalent was "shimose". Common lyddite shells "detonated" and fragmented into small pieces in all directions, with no incendiary effect. For maximum destructive effect the explosion needed to be delayed until the shell had penetrated its target.
Early shells had walls of the same thickness for the whole length, later shells had walls thicker at the base and thinning towards the nose. This was found to give greater strength and provide more space for explosive. Later shells had
4 c.r. heads, more pointed and hence streamlined than earlier 2 c.r.h. designs.
Proper detonation of a lyddite shell would show black to grey smoke, or white from the steam of a water detonation. Yellow smoke indicated simple explosion rather than detonation, and failure to reliably detonate was a problem with lyddite, especially in its earlier usage. To improve the detonation "exploders" with a small quantity of picric powder or even of TNT (in smaller shells, 3 pdr, 12 pdr – 4.7 inch) was loaded between the fuze and the main lyddite filling or in a thin tube running through most of the shell's length.
Lyddite presented a major safety problem because it reacted dangerously with metal bases. This required that the interior of shells had to be varnished, the exterior had to be painted with leadless paint and the fuze-hole had to be made of a leadless alloy. Fuzes containing any lead could not be used with it.
When World War I began Britain was replacing lyddite with modern "high explosive" (HE) such as TNT. After World War I the term "common lyddite" was dropped, and remaining stocks of lyddite-filled shells were referred to as HE (high explosive) shell filled lyddite. Hence "common" faded from use, replaced by "HE" as the explosive shell designation.
Common lyddite shells in British service were painted yellow, with a red ring behind the nose to indicate the shell had been filled.
Mine shell
The mine shell is a particular form of HE shell developed for use in small caliber weapons such as 20 mm to 30 mm cannon. Small HE shells of conventional design can contain only a limited amount of explosive. By using a thin-walled steel casing of high tensile strength, a larger explosive charge can be used. Most commonly the explosive charge also was a more expensive but higher-detonation-energy type.
The ''mine shell'' concept was invented by the Germans in the Second World War primarily for use in aircraft guns intended to be fired at opposing aircraft. Mine shells produced relatively little damage due to fragments, but a much more powerful blast. The
aluminium
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...
structures and skins of Second World War
aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines ...
were readily damaged by this greater level of blast.
Shrapnel shells
Shrapnel shell
Shrapnel shells were anti-personnel artillery munitions which carried many individual bullets close to a target area and then ejected them to allow them to continue along the shell's trajectory and strike targets individually. They relied almo ...
s are an anti-personnel munition which delivered large numbers of
bullet
A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. Bullets are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax. Bullets are made in various shapes and co ...
s at ranges far greater than rifles or machine guns could attain – up to 6,500 yards by 1914. A typical shrapnel shell as used in World War I was streamlined, 75 mm (3 in) in diameter and contained approximately 300 lead–antimony balls (bullets), each around 1/2-inch in diameter. Shrapnel used the principle that the bullets encountered much less air resistance if they travelled most of their journey packed together in a single streamlined shell than they would if they travelled individually, and could hence attain a far greater range.
The gunner set the shell's
time fuze so that it was timed to burst as it was angling down towards the ground just before it reached its target (ideally about 150 yards before, and 60–100 feet above the ground). The fuze then ignited a small "bursting charge" in the base of the shell which fired the balls forward out of the front of the shell case, adding 200–250 ft/second to the existing velocity of 750–1200 ft/second. The shell body dropped to the ground mostly intact and the bullets continued in an expanding cone shape before striking the ground over an area approximately 250 yards × 30 yards in the case of the US 3-inch shell.
[Douglas T Hamilton]
"Shrapnel Shell Manufacture. A Comprehensive Treatise.". New York: Industrial Press, 1915, Page 13
/ref> The effect was of a large shotgun blast just in front of and above the target, and was deadly against troops in the open. A trained gun team could fire 20 such shells per minute, with a total of 6,000 balls, which compared very favorably with rifles and machine-guns.
However, shrapnel's relatively flat trajectory (it depended mainly on the shell's velocity for its lethality, and was lethal only in the forward direction) meant that it could not strike trained troops who avoided open spaces and instead used dead ground (dips), shelters, trenches, buildings, and trees for cover. It was of no use in destroying buildings or shelters. Hence, it was replaced during World War I by the high-explosive shell, which exploded its fragments in all directions (and thus more difficult to avoid) and could be fired by high-angle weapons, such as howitzers.
Cluster and sub-munition
Cluster shells are a type of carrier shell or cargo munition. Like cluster bomb
A cluster munition is a form of air-dropped or ground-launched explosive weapon that releases or ejects smaller submunitions. Commonly, this is a cluster bomb that ejects explosive bomblets that are designed to kill personnel and destroy vehicl ...
s, an artillery shell may be used to scatter smaller sub-munitions, including anti-personnel grenade
A grenade is an explosive weapon typically thrown by hand (also called hand grenade), but can also refer to a shell (explosive projectile) shot from the muzzle of a rifle (as a rifle grenade) or a grenade launcher. A modern hand grenade genera ...
s, anti-tank top-attack munitions, and landmines
A land mine is an explosive device concealed under or on the ground and designed to destroy or disable enemy targets, ranging from combatants to vehicles and tanks, as they pass over or near it. Such a device is typically detonated automati ...
. These are generally far more lethal against both armor
Armour (British English) or armor (American English; see spelling differences) is a covering used to protect an object, individual, or vehicle from physical injury or damage, especially direct contact weapons or projectiles during combat, or fr ...
and infantry
Infantry is a military specialization which engages in ground combat on foot. Infantry generally consists of light infantry, mountain infantry, motorized infantry & mechanized infantry, airborne infantry, air assault infantry, and marine i ...
than simple high-explosive shells, since the multiple munitions create a larger kill zone and increase the chance of achieving the direct hit necessary to kill armor. Many modern armies make significant use of cluster munition
A cluster munition is a form of air-dropped or ground-launched explosive weapon that releases or ejects smaller submunitions. Commonly, this is a cluster bomb that ejects explosive bomblets that are designed to kill personnel and destroy vehicl ...
s in their artillery batteries.
Artillery-scattered mines allow for the quick deployment of minefield
A land mine is an explosive device concealed under or on the ground and designed to destroy or disable enemy targets, ranging from combatants to vehicles and tanks, as they pass over or near it. Such a device is typically detonated automati ...
s into the path of the enemy without placing engineering units at risk, but artillery delivery may lead to an irregular and unpredictable minefield with more unexploded ordnance than if mines were individually placed.
Signatories of the Convention on Cluster Munitions
The Convention on Cluster Munitions (CCM) is an international treaty that prohibits all use, transfer, production, and stockpiling of cluster bombs, a type of explosive weapon which scatters submunitions ("bomblets") over an area. Additionally, ...
have accepted restrictions on the use of cluster munitions, including artillery shells: the treaty requires that a weapon so defined must contain nine or fewer submunitions, which must each weigh more than 4 kilograms, be capable of detecting and engaging a single target, and contain electronic self-destruct and self-deactivation systems. Submunitions which weigh 20 kg or more are not restricted.
Chemical
Chemical shells contain just a small explosive charge to burst the shell, and a larger quantity of a chemical agent
A chemical weapon (CW) is a specialized munition that uses chemicals formulated to inflict death or harm on humans. According to the Organisation for the Prohibition of Chemical Weapons (OPCW), this can be any chemical compound intended as a ...
or riot control agent
Riot control measures are used by law enforcement, military, paramilitary or security forces to control, disperse, and arrest people who are involved in a riot, unlawful demonstration or unlawful protest.
If a riot is spontaneous and irration ...
of some kind, in either liquid, gas or powdered form. In some cases such as the M687
The M687 was an American 155 mm binary sarin chemical artillery shell. The design was standardized in 1976 and production began on December 16, 1987 at Pine Bluff Arsenal, Pine Bluff, Arkansas. Production was halted three years later, following th ...
Sarin gas shell, the payload is stored as two precursor chemicals which are mixed after the shell is fired. Some examples designed to deliver powdered chemical agents, such as the M110 155mm Cartridge
The M110 155mm Projectile is an artillery shell used by the U.S. Army and U.S. Marine Corps. The M110 was originally designed as a chemical artillery round to deliver blister agents via howitzer as a replacement for the World War I-era 75mm chemic ...
, were later repurposed as smoke/incendiary rounds containing powdered white phosphorus
Elemental phosphorus can exist in several allotropes, the most common of which are white and red solids. Solid violet and black allotropes are also known. Gaseous phosphorus exists as diphosphorus and atomic phosphorus.
White phosphorus
White ...
.
Chemical shells were most commonly employed during the First World War
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
. Use of chemical agents of all kinds has been forbidden by numerous international treaties starting with the 1925 Geneva Protocol
The Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or other Gases, and of Bacteriological Methods of Warfare, usually called the Geneva Protocol, is a treaty prohibiting the use of chemical and biological weapons in ...
(not to be confused with the Geneva Convention
upright=1.15, Original document in single pages, 1864
The Geneva Conventions are four treaties, and three additional protocols, that establish international legal standards for humanitarian treatment in war. The singular term ''Geneva Conven ...
), with the 1993 Chemical Weapons Convention
The Chemical Weapons Convention (CWC), officially the Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction, is an arms control treaty administered by the Organisation for ...
being the most modern treaty which also outlaws production, stockpiling and transfer of such weapons. All signatories have renounced the use of both lethal chemical agents and incapacitating agents in warfare.
Nuclear artillery
Nuclear artillery shells are used to provide battlefield scale nuclear weapons for tactical use. These range from the relatively small 155 mm shell to the 406 mm shell used by heavy battleship cannon and shore defense units equipped with the same guns.
Non-lethal shells
Not all shells are designed to kill or destroy. The following types are designed to achieve particular non-lethal effects. They are not completely harmless: smoke and illumination shells can accidentally start fires, and impact by the discarded carrier of all three types can wound or kill personnel, or cause minor damage to property.
Smoke
Smoke shells are used to create smoke screen
A smoke screen is smoke released to mask the movement or location of military units such as infantry, tanks, aircraft, or ships.
Smoke screens are commonly deployed either by a canister (such as a grenade) or generated by a vehicle (such as ...
s to mask movements of friendly forces or disorient enemies, or to mark specific areas. The main types are bursting (using a payload powdered chemicals) and base ejection (delivering three or four smoke canisters which are deployed from the rear of the shell prior to impact, or a single canister containing submunitions distributed via a bursting charge). Base ejection shells are a type of carrier shell or cargo munition.
Base ejection smoke is usually white, however, colored smoke has been used for marking purposes. The original canisters typically used hexachloroethane
Hexachloroethane, also known as perchloroethane is the organochlorine compound with the chemical formula . It is white solid at room temperature with a camphor-like odor. It has been used by the military in smoke compositions, such as base-eject ...
-zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodi ...
(HC), modern ones use red phosphorus
Elemental phosphorus can exist in several allotropes, the most common of which are white and red solids. Solid violet and black allotropes are also known. Gaseous phosphorus exists as diphosphorus and atomic phosphorus.
White phosphorus
White ...
because of its multi-spectral properties. However, other compounds have been used; in World War II, Germany used oleum
Oleum (Latin ''oleum'', meaning oil), or fuming sulfuric acid, is a term referring to solutions of various compositions of sulfur trioxide in sulfuric acid, or sometimes more specifically to disulfuric acid (also known as pyrosulfuric acid). Ole ...
(fuming sulfuric acid) and pumice
Pumice (), called pumicite in its powdered or dust form, is a volcanic rock that consists of highly vesicular rough-textured volcanic glass, which may or may not contain crystals. It is typically light-colored. Scoria is another vesicular vol ...
.
Due to the nature of their payload, powder smoke shells using white phosphorus
Elemental phosphorus can exist in several allotropes, the most common of which are white and red solids. Solid violet and black allotropes are also known. Gaseous phosphorus exists as diphosphorus and atomic phosphorus.
White phosphorus
White ...
in particular have a secondary effect as incendiary weapons, though they are not as effective in this role as dedicated weapons using thermite
Thermite () is a pyrotechnic composition of metal powder and metal oxide. When ignited by heat or chemical reaction, thermite undergoes an exothermic reduction-oxidation (redox) reaction. Most varieties are not explosive, but can create brief ...
.
Illumination
Modern illuminating shells are a type of carrier shell or cargo munition. Those used in World War I were shrapnel pattern shells ejecting small burning "pots".
A modern illumination shell has a time fuze that ejects a flare "package" through the base of the carrier shell at a standard height above ground (typically about 600 metres), from where it slowly falls beneath a non-flammable parachute
A parachute is a device used to slow the motion of an object through an atmosphere by creating drag or, in a ram-air parachute, aerodynamic lift. A major application is to support people, for recreation or as a safety device for aviators, who ...
, illuminating the area below. The ejection process also initiates a pyrotechnic
Pyrotechnics is the science and craft of creating such things as fireworks, safety matches, oxygen candles, explosive bolts and other fasteners, parts of automotive airbags, as well as gas-pressure blasting in mining, quarrying, and demolition. ...
flare emitting white or "black" infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
light.
Typically illumination flares burn for about 60 seconds. These are also known as ''starshell'' or ''star shell''. Infrared illumination is a more recent development used to enhance the performance of night-vision devices. Both white- and black-light illuminating shells may be used to provide continuous illumination over an area for a period of time and may use several dispersed aimpoints to illuminate a large area. Alternatively, firing single illuminating shells may be coordinated with the adjustment of HE shell fire onto a target.
Colored flare shells have also been used for target marking and other signaling purposes.
Carrier
The carrier shell is simply a hollow carrier equipped with a fuze that ejects the contents at a calculated time. They are often filled with leaflets (see external links), but can be filled with anything that meets the weight restrictions and is able to withstand the shock of firing. Famously, on Christmas Day 1899 during the siege of Ladysmith
The siege of Ladysmith was a protracted engagement in the Second Boer War, taking place between 2 November 1899 and 28 February 1900 at Ladysmith, Natal.
Background
As war with the Boer republics appeared likely in June 1899, the War Office ...
, the Boer
Boers ( ; af, Boere ()) are the descendants of the Dutch-speaking Free Burghers of the eastern Cape Colony, Cape frontier in Southern Africa during the 17th, 18th, and 19th centuries. From 1652 to 1795, the Dutch East India Company controll ...
s fired into Ladysmith a carrier shell without a fuze, which contained a Christmas pudding
Christmas pudding is sweet dried-fruit pudding traditionally served as part of Christmas dinner in Britain and other countries to which the tradition has been exported. It has its origins in medieval England, with early recipes making use of d ...
, two Union Flag
The Union Jack, or Union Flag, is the ''de facto'' national flag of the United Kingdom. Although no law has been passed making the Union Flag the official national flag of the United Kingdom, it has effectively become such through precedent. ...
s and the message "compliments of the season". The shell is still kept in the museum at Ladysmith.
Proof shot
A proof shot
A proof test is a form of stress test to demonstrate the fitness of a load-bearing structure. An individual proof test may apply only to the unit tested, or to its design in general for mass-produced items. Such a structure is often subjected t ...
is not used in combat but to confirm that a new gun barrel can withstand operational stresses. The proof shot is heavier than a normal shot or shell, and an oversize propelling charge is used, subjecting the barrel to greater than normal stress. The proof shot is inert (no explosive or functioning filling) and is often a solid unit, although water, sand or iron powder filled versions may be used for testing the gun mounting. Although the proof shot resembles a functioning shell (of whatever sort), so that it behaves as a real shell in the barrel, it is not aerodynamic as its job is over once it has left the muzzle of the gun. Consequently, it travels a much shorter distance and is usually stopped by an earth bank for safety measures.
The gun, operated remotely for safety in case it fails, fires the proof shot, and is then inspected for damage. If the barrel passes the examination, "proof mark
A proof test is a form of stress test to demonstrate the fitness of a load-bearing structure. An individual proof test may apply only to the unit tested, or to its design in general for mass-produced items. Such a structure is often subjected t ...
s" are added to the barrel. The gun can be expected to handle normal ammunition, which subjects it to less stress than the proof shot, without being damaged.
Guided shells
Guided or "smart" ammunition features some method of guiding itself post-launch, usually through the addition of steering fins that alter its trajectory in an unpowered glide. Due to their much higher cost, they have yet to supplant unguided munitions in all applications.
Image:XM982 Excalibur inert.jpg, M982 Excalibur
The M982 Excalibur (previously XM982) is a 155 mm extended-range guided artillery shell developed in a collaborative effort between the U.S. Army Research Laboratory (ARL) and the United States Army Armament Research, Development and Engineering ...
, a GPS guided artillery shell
Image:Copperhead and tank.JPEG, M712 Copperhead
The M712 Copperhead is a 155 mm caliber cannon-launched guided projectile. It is
a fin-stabilized, terminally laser guided, explosive shell intended to engage hard point targets such as tanks, self-propelled howitzers or other high-value targe ...
, a laser guided artillery shell, approaches a target tank
Image:SMArt 155 SubMunition for Artillery 2 cutaway.jpg, SMArt 155
SMArt 155 is a German 155 mm artillery round, designed for a long range, indirect fire top attack role against armoured vehicles. The SMArt carrier shell contains two submunitions with infrared sensor and millimeter wave radar, which descen ...
, an anti-armor shell containing two autonomous, sensor-guided, fire-and-forget
Fire-and-forget is a type of missile guidance which does not require further external intervention after launch such as illumination of the target or wire guidance, and can hit its target without the launcher being in line-of-sight of the targe ...
submunitions
File:XM1156-PGK.svg, M1156 Precision Guidance Kit
The M1156 Precision Guidance Kit (PGK), formerly XM1156, is a U.S. Army-designed precision guidance system to turn existing 155 mm artillery shells into smart weapons. , an add-on GPS guidance system for artillery shells
Unexploded shells
The fuze
In military munitions, a fuze (sometimes fuse) is the part of the device that initiates function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fuze d ...
of a shell has to keep the shell safe from accidental functioning during storage, due to (possibly) rough handling, fire, etc. It also has to survive the violent launch through the barrel, then reliably function at the appropriate moment. To do this it has a number of arming mechanisms which are successively enabled under the influence of the firing sequence.
Sometimes, one or more of these arming mechanisms fail, resulting in a projectile that is unable to detonate. More worrying (and potentially far more hazardous) are fully armed shells on which the fuze fails to initiate the HE firing. This may be due to a shallow trajectory of fire, low-velocity firing or soft impact conditions. Whatever the reason for failure, such a shell is called a ''blind'' or ''unexploded ordnance ( UXO)'' (the older term, "dud", is discouraged because it implies that the shell ''cannot'' detonate.) Blind shells often litter old battlefields; depending on the impact velocity, they may be buried some distance into the earth, all the while remaining potentially hazardous. For example, antitank ammunition with a piezoelectric fuze can be detonated by relatively light impact to the piezoelectric element, and others, depending on the type of fuze used, can be detonated by even a small movement. The battlefields of the First World War still claim casualties today from leftover munitions. Modern electrical and mechanical fuzes are highly reliable: if they do not arm correctly, they keep the initiation train out of line or (if electrical in nature) discharge any stored electrical energy.
See also
* Ammunition
Ammunition (informally ammo) is the material fired, scattered, dropped, or detonated from any weapon or weapon system. Ammunition is both expendable weapons (e.g., bombs, missiles, grenades, land mines) and the component parts of other weap ...
* Artillery
Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...
* Bombshell (slang)
The term bombshell is a forerunner to the term "sex symbol" and originally used to describe popular women regarded as very attractive. The '' Online Etymology Dictionary'' by Douglas Harper attests the usage of the term in this meaning since 1942 ...
* Cartridge (firearms)
A cartridge or a round is a type of pre-assembled firearm ammunition packaging a projectile (bullet, shot, or slug), a propellant substance (usually either smokeless powder or black powder) and an ignition device (primer) within a metallic ...
References
Sources
* Douglas T. Hamilton
"High-explosive shell manufacture; a comprehensive treatise"
New York: Industrial Press, 1916.
* Douglas T. Hamilton
"Shrapnel Shell Manufacture. A Comprehensive Treatise"
New York: Industrial Press, 1915.
* Hogg, O. F. G. 1970. "Artillery: its origin, heyday and decline". London: C. Hurst and Company.
External links
"What Happens When a Shell Bursts," ''Popular Mechanics'', April 1906, p. 408
– with photograph of exploded shell reassembled
* : A website about airdropped, shelled or rocket fired propaganda leaflets. Example artillery shells for spreading propaganda.
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Artillery ammunition
Explosive projectiles
Chinese inventions
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