Finnish smokeless powder![H110 Smokeless Pistol Powder Macro](https://upload.wikimedia.org/wikipedia/commons/f/f3/H110_Smokeless_Pistol_Powder_Macro.png)
Smokeless powder is a type of
propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...
used in
firearm
A firearm is any type of gun designed to be readily carried and used by an individual. The term is legally defined further in different countries (see Legal definitions).
The first firearms originated in 10th-century China, when bamboo tubes ...
s and
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 ...
that produces less smoke and less
fouling
Fouling is the accumulation of unwanted material on solid surfaces. The fouling materials can consist of either living organisms (biofouling) or a non-living substance (inorganic or organic). Fouling is usually distinguished from other surf ...
when fired compared to
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). ...
("black powder"). The
combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combusti ...
products are mainly gaseous, compared to around 55% solid products (mostly
potassium carbonate
Potassium carbonate is the inorganic compound with the formula K2 CO3. It is a white salt, which is soluble in water. It is deliquescent, often appearing as a damp or wet solid. Potassium carbonate is mainly used in the production of soap and gl ...
,
potassium sulfate
Potassium sulfate (US) or potassium sulphate (UK), also called sulphate of potash (SOP), arcanite, or archaically potash of sulfur, is the inorganic compound with formula K2SO4, a white water-soluble solid. It is commonly used in fertilizers, pro ...
, and
potassium sulfide) for black powder.
In addition, smokeless powder does not leave the thick, heavy
fouling
Fouling is the accumulation of unwanted material on solid surfaces. The fouling materials can consist of either living organisms (biofouling) or a non-living substance (inorganic or organic). Fouling is usually distinguished from other surf ...
of
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance ...
material associated with black powder that causes rusting of the barrel. Despite its name, smokeless powder is not completely free of
smoke
Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product ...
;
while there may be little noticeable smoke from small-arms ammunition, smoke from artillery fire can be substantial.
Originally invented in 1884 by
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 ...
, the most common formulations are based on
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 ...
, but the term was also used to describe various
picrate
A picrate is a salt containing the anion (O2N)3C6H2O− or an ester derivative of the picrate anion. These salts are often produced by reactions of picric acid (2,4,6-trinitrophenol).
The picrate ion is intensely yellow, although many of its salt ...
mixtures with
nitrate
Nitrate is a polyatomic ion
A polyatomic ion, also known as a molecular ion, is a covalent bonded set of two or more atoms, or of a metal complex, that can be considered to behave as a single unit and that has a net charge that is not zer ...
,
chlorate
The chlorate anion has the formula ClO3-. In this case, the chlorine atom is in the +5 oxidation state. "Chlorate" can also refer to chemical compounds containing this anion; chlorates are the salts of chloric acid. "Chlorate", when followed by ...
, or
dichromate oxidizers during the late 19th century, before the advantages of nitrocellulose became evident.
Smokeless powders are typically classified as division 1.3 explosives under the
UN ''
Recommendations on the Transport of Dangerous Goods
The ''UN Recommendations on the Transport of Dangerous Goods'' are contained in thprepared by the Subcommittee of Experts on the Transport of Dangerous Goods of the United Nations Economic and Social Council (ECOSOC). They cover the transport of d ...
– Model Regulations'', regional regulations (such as
ADR ADR or adr may refer to:
Computing
* Asynchronous DRAM refresh, an approach for persistent memory found in some Intel Xeon processors
* The adr microformat, part of the hCard microformat
* Architectural decision record
* Action–domain–respond ...
) and national regulations. However, they are used as
solid propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...
s; in normal use, they undergo
deflagration
Deflagration (Lat: ''de + flagrare'', "to burn down") is subsonic combustion in which a pre-mixed flame propagates through a mixture of fuel and oxidizer. Deflagrations can only occur in pre-mixed fuels. Most fires found in daily life are diffu ...
rather than
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 ...
.
Smokeless powder made autoloading firearms with many moving parts feasible (which would otherwise jam or seize under heavy black powder fouling). Smokeless powder allowed the development of modern semi- and fully automatic firearms and lighter breeches and barrels for artillery.
History
Before the widespread introduction of smokeless powder the use of gunpowder or black powder caused many problems on the battlefield. Military commanders 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 ...
reported difficulty with giving orders on a battlefield obscured by the smoke of firing. Visual signals could not be seen through the thick smoke from the
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). ...
used by the guns. Unless there was a strong wind, after a few shots, soldiers using gunpowder ammunition would have their view obscured by a huge cloud of smoke.
Sniper
A sniper is a military/paramilitary marksman who engages targets from positions of concealment or at distances exceeding the target's detection capabilities. Snipers generally have specialized training and are equipped with high-precision r ...
s or other concealed shooters were given away by a cloud of smoke over the firing position. Gunpowder produces lower pressures and is about three times less powerful when compared to smokeless powder.
Gunpowder is also hygroscopic (i.e., it attracts moisture from the air), making cleaning mandatory after every use. Likewise, gunpowder's tendency to produce severe
fouling
Fouling is the accumulation of unwanted material on solid surfaces. The fouling materials can consist of either living organisms (biofouling) or a non-living substance (inorganic or organic). Fouling is usually distinguished from other surf ...
causes actions to jam and often makes reloading difficult.
Nitroglycerine and guncotton
Nitroglycerine
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating ...
was synthesized by the Italian
chemist
A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties. Chemists carefully describe th ...
Ascanio Sobrero
Ascanio Sobrero (12 October 1812 – 26 May 1888) was an Italian chemist, born in Casale Monferrato. He was studying under Théophile-Jules Pelouze at the University of Turin, who had worked with the explosive material guncotton.
He studied me ...
in 1847.
It was subsequently developed and manufactured by Alfred Nobel as an industrial explosive, but even then it was unsuitable as a propellant: despite its energetic and smokeless qualities, it
detonates instead of
deflagrating smoothly, making it more liable to shatter a gun, rather than propel a projectile out of it. Nitroglycerine is also highly sensitive, making it unfit to be carried in battlefield conditions.
A major step forward was the invention of
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, by German 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
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 once again somewhat more unstable. John Taylor obtained an English patent for guncotton; and John Hall & Sons began manufacture in
Faversham
Faversham is a market town in Kent, England, from London and from Canterbury, next to the Swale, a strip of sea separating mainland Kent from the Isle of Sheppey in the Thames Estuary. It is close to the A2, which follows an ancient British t ...
.
English interest languished 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 propellent, but it too was dangerous under field conditions, and guns that could fire thousands of rounds using black powder would reach the end of 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.
Improvements
An extruded stick powder
In 1863,
Prussia
Prussia, , Old Prussian: ''Prūsa'' or ''Prūsija'' was a German state on the southeast coast of the Baltic Sea. It formed the German Empire under Prussian rule when it united the German states in 1871. It was ''de facto'' dissolved by an em ...
n artillery captain Johann F. E. Schultze patented a small-arms propellant of nitrated hardwood impregnated with
saltpeter
Potassium nitrate is a chemical compound with the chemical formula . This alkali metal nitrate salt is also known as Indian saltpetre (large deposits of which were historically mined in India). It is an ionic salt of potassium ions K+ and nitrat ...
or
barium nitrate
Barium nitrate is the inorganic compound with the chemical formula Ba( NO3)2. It, like most barium salts, is colorless, toxic, and water-soluble. It burns with a green flame and is an oxidizer; the compound is commonly used in pyrotechnics.
Man ...
. Prentice received an 1866 patent for a sporting powder of nitrated paper manufactured at Stowmarket, but ballistic uniformity suffered as the paper absorbed atmospheric moisture. In 1871, Frederick Volkmann received an Austrian patent for a colloided version of Schultze powder called ''Collodin'', which he manufactured near Vienna for use in sporting firearms. Austrian patents were not published at the time, and the Austrian Empire considered the operation a violation of the government monopoly on explosives manufacture and closed the Volkmann factory in 1875.
In 1882, the Explosives Company at Stowmarket patented an improved formulation of nitrated cotton gelatinised by ether-alcohol with nitrates of
potassium
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosphe ...
and
barium
Barium is a chemical element with the symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element.
Th ...
. These propellants were suitable for shotguns but not rifles,
because
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 ...
results in resistance to a smooth expansion of the gas, which is reduced in
smoothbore
A smoothbore weapon is one that has a barrel without rifling. Smoothbores range from handheld firearms to powerful tank guns and large artillery mortars.
History
Early firearms had smoothly bored barrels that fired projectiles without signi ...
shotguns.
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
Poudre B was the first practical smokeless gunpowder created in 1884. It was perfected between 1882 and 1884 at "Laboratoire Central des Poudres et Salpêtres" in Paris, France. Originally called "Poudre V" from the name of the inventor, Paul Vi ...
(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 ...
)
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 nitrocellulose 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
The Lebel Model 1886 rifle (French: ''Fusil Modèle 1886 dit "Fusil Lebel"'') also known as the ''"Fusil Mle 1886 M93"'', after a bolt modification was added in 1893, is an 8 mm bolt-action infantry rifle that entered service in the French A ...
chambered in
8×50mmR Lebel
The 8×50mmR Lebel (8mm Lebel) (designated as the 8 × 51 R Lebel by the C.I.P.) rifle cartridge was the first smokeless powder cartridge to be made and adopted by any country. It was introduced by France in 1886. Formed by necking down the 11 ...
.
It was passed through rollers to form paper thin sheets, which were cut into flakes of the desired size.
The resulting
propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or other motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the e ...
, today known as ''pyrocellulose'', contains somewhat less
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
than
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 ...
and is less volatile. A particularly good feature of the propellant is that it will not detonate unless it is compressed, making it very safe to handle under normal conditions. 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 shots practicable. Since less powder was needed to propel a bullet, the
cartridge
Cartridge may refer to:
Objects
* Cartridge (firearms), a type of modern ammunition
* ROM cartridge, a removable component in an electronic device
* Cartridge (respirator), a type of filter used in respirators
Other uses
* Cartridge (surname), a ...
could be made smaller and lighter. This allowed troops to carry more ammunition for the same weight. Also, it would burn even when wet. Black powder ammunition had to be kept dry and was almost always stored and transported in watertight cartridges. Other European countries swiftly followed and started using their own versions of Poudre B, the first being Germany and Austria, 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 oxidiz ...
as a stabilizer in 1888.
Meanwhile, in 1887,
Alfred Nobel
Alfred Bernhard Nobel ( , ; 21 October 1833 – 10 December 1896) was a Swedes, Swedish chemist, engineer, inventor, businessman, and Philanthropy, philanthropist. He is best known for having bequeathed his fortune to establish the Nobel ...
obtained an English patent for a smokeless gunpowder he called
Ballistite
Ballistite is a smokeless propellant made from two high explosives, nitrocellulose and nitroglycerine. It was developed and patented by Alfred Nobel in the late 19th century.
Military adoption
Alfred Nobel patented https://www.nobelprize.org/alf ...
. In this propellant the fibrous structure of cotton (nitro-cellulose) was destroyed by a
nitroglycerine
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating ...
solution instead of a solvent.
In England in 1889, a similar powder was patented by
Hiram Maxim
Sir Hiram Stevens Maxim (5 February 1840 – 24 November 1916) was an American-British inventor best known as the creator of the first automatic machine gun, the Maxim gun. Maxim held patents on numerous mechanical devices such as hair-curl ...
, and in the United States in 1890 by
Hudson Maxim
Hudson Maxim (February 3, 1853 – May 6, 1927), was a U.S. inventor and chemist who invented a variety of explosives, including smokeless gunpowder, Thomas Edison referred to him as "the most versatile man in America". He was the brother ...
.
Ballistite was patented in the United States in 1891. The Germans adopted ballistite for naval use in 1898, calling it WPC/98. The Italians adopted it as ''filite'', in cord instead of flake form, but realising its drawbacks changed to a formulation with nitroglycerine they called ''solenite''. In 1891 the Russians tasked the chemist
Mendeleev
Dmitri Ivanovich Mendeleev (sometimes transliterated as Mendeleyev or Mendeleef) ( ; russian: links=no, Дмитрий Иванович Менделеев, tr. , ; 8 February Old_Style_and_New_Style_dates">O.S._27_January.html" ;"title="O ...
with finding a suitable propellant. He created nitrocellulose gelatinised by ether-alcohol, which produced more
nitrogen
Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...
and more uniform colloidal structure than the French use of nitro-cottons
in Poudre B. He called it
pyrocollodion Pyrocollodion is a smokeless powder invented by Dmitri Mendeleev. A variant of nitrocellulose family of compounds, it was discovered by Dmitri Mendeleev in 1892. He and proposed its use as a replacement for gunpowder in the Russian Navy. This ...
.
Close-up of Cordite filaments in a rifle cartridge (manufactured in 1964)">.303 British rifle cartridge (manufactured in 1964)
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 (Nos 5614 and 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%
nitroglycerine
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating ...
, 37%
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 ...
and 3% mineral jelly. A modified version, Cordite MD, entered service in 1901, with the guncotton percentage increased to 65% and nitroglycerine reduced to 30%. This change reduced the combustion temperature and hence erosion and barrel wear. Cordite's advantages over gunpowder were reduced maximum pressure in the chamber (hence lighter breeches, etc.) but longer high pressure. Cordite could be made in any desired shape or size.
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.
The Anglo-American Explosives Company began manufacturing its shotgun powder in
Oakland, New Jersey
Oakland is a borough in Bergen County, New Jersey, United States and a suburb of New York City. As of the 2010 United States census, the borough's population was 12,754,[DuPont
DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...]
began producing guncotton at
Carneys Point Township, New Jersey in 1891.
Charles E. Munroe of the
Naval Torpedo Station
The Naval Undersea Warfare Center (NUWC) is the United States Navy's full-spectrum research, development, test and evaluation, engineering and fleet support center for submarines, autonomous underwater systems, and offensive and defensive weapons ...
in
Newport, Rhode Island
Newport is an American seaside city on Aquidneck Island in Newport County, Rhode Island. It is located in Narragansett Bay, approximately southeast of Providence, Rhode Island, Providence, south of Fall River, Massachusetts, south of Boston, ...
patented a formulation of guncotton colloided with nitrobenzene, called ''Indurite'', in 1891.
Several United States firms began producing smokeless powder when
Winchester Repeating Arms Company
The Winchester Repeating Arms Company was a prominent American manufacturer of repeating firearms and ammunition. The firm was established in 1866 by Oliver Winchester and was located in New Haven, Connecticut. The firm went into receivership ...
started loading sporting cartridges with Explosives Company powder in 1893.
California Powder Works
California Powder Works was the first American explosive powder manufacturing company west of the Rocky Mountains. When the outbreak of the Civil War cut off supplies of gunpowder to California's mining and road-building industries, a local manufac ...
began producing a mixture of nitroglycerine and
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 ...
with
ammonium picrate
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 ...
as ''Peyton Powder'', Leonard Smokeless Powder Company began producing nitroglycerine–nitrocellulose ''Ruby'' powders,
Laflin & Rand negotiated a license to produce ''Ballistite'', and DuPont started producing smokeless shotgun powder. The
United States Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...
evaluated 25 varieties of smokeless powder and selected ''Ruby'' and ''Peyton Powders'' as the most suitable for use in the
Krag–Jørgensen
The Krag–Jørgensen is a repeating bolt-action rifle designed by the Norwegians Ole Herman Johannes Krag and Erik Jørgensen in the late 19th century. It was adopted as a standard arm by Norway, Denmark, and the United States. About 300 wer ...
service rifle. ''Ruby'' was preferred, because tin-plating was required to protect brass cartridge cases from
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 ...
in the ''Peyton Powder''. Rather than paying the required royalties for ''Ballistite'', Laflin & Rand financed Leonard's reorganization as the American Smokeless Powder Company. United States Army Lieutenant Whistler assisted American Smokeless Powder Company factory superintendent Aspinwall in formulating an improved powder named W.A. for their efforts. W.A. smokeless powder was the standard for United States military service rifles from 1897 until 1908.
In 1897, United States Navy Lieutenant
John Bernadou
John Baptiste Bernadou (November 14, 1858 – October 2, 1908) was an officer in the United States Navy during the Spanish–American War. Born in Philadelphia, Bernadou graduated from the Naval Academy in 1880. He was promoted ten numbers for ga ...
patented a nitrocellulose powder colloided with ether-alcohol.
The Navy licensed or sold patents for this formulation to
DuPont
DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...
and the California Powder Works while retaining manufacturing rights for the
Naval Powder Factory, Indian Head, Maryland
Naval Surface Warfare Center, Indian Head Division (NSWC IHD)—also known as Naval Support Facility Indian Head—is a United States United States Navy, naval United States Armed Forces, military installation in Charles County, Maryland, Charles ...
constructed in 1900. The United States Army adopted the Navy single-base formulation in 1908 and began manufacture at
Picatinny Arsenal
The Picatinny Arsenal ( or ) is an American military research and manufacturing facility located on of land in Jefferson and Rockaway Township in Morris County, New Jersey, United States, encompassing Picatinny Lake and Lake Denmark. The Ars ...
.
By that time Laflin & Rand had taken over the American Powder Company to protect their investment, and Laflin & Rand had been purchased by
DuPont
DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...
in 1902.
Upon securing a 99-year lease of the Explosives Company in 1903, DuPont enjoyed use of all significant smokeless powder patents in the United States, and was able to optimize production of smokeless powder.
When government anti-trust action forced divestiture in 1912, DuPont retained the nitrocellulose smokeless powder formulations used by the United States military and released the double-base formulations used in sporting ammunition to the reorganized
Hercules Powder Company
Hercules, Inc. was a chemical and munitions manufacturing company based in Wilmington, Delaware, United States, incorporated in 1912 as the Hercules Powder Company following the breakup of the DuPont explosives monopoly by the U.S. Circuit ...
. These newer and more powerful propellants were more stable and thus safer to handle than Poudre B.
Characteristics
The properties of the propellant are greatly influenced by the size and shape of its pieces. The specific surface area of the propellant influences the speed of burning, and the size and shape of the particles determine the specific surface area. By manipulation of the shape it is possible to influence the burning rate and hence the rate at which pressure builds during combustion. Smokeless powder burns only on the surfaces of the pieces. Larger pieces burn more slowly, and the burn rate is further controlled by flame-deterrent coatings that retard burning slightly. The intent is to regulate the burn rate so that a more or less constant pressure is exerted on the propelled projectile as long as it is in the barrel so as to obtain the highest velocity. The perforations stabilize the burn rate because as the outside burns inward (thus shrinking the burning surface area) the inside is burning outward (thus increasing the burning surface area, but faster, so as to fill up the increasing volume of barrel presented by the departing projectile).
Fast-burning
pistol
A pistol is a handgun, more specifically one with the chamber integral to its gun barrel, though in common usage the two terms are often used interchangeably. The English word was introduced in , when early handguns were produced in Europe, an ...
powders are made by extruding shapes with more area such as flakes or by flattening the spherical granules. Drying is usually performed under a vacuum. The solvents are condensed and recycled. The granules are also coated with
graphite
Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large ...
to prevent static electricity sparks from causing undesired ignitions.
Smokeless powder does not leave the thick, heavy
fouling
Fouling is the accumulation of unwanted material on solid surfaces. The fouling materials can consist of either living organisms (biofouling) or a non-living substance (inorganic or organic). Fouling is usually distinguished from other surf ...
of
hygroscopic
Hygroscopy is the phenomenon of attracting and holding water molecules via either absorption or adsorption from the surrounding environment, which is usually at normal or room temperature. If water molecules become suspended among the substance ...
material associated with black powder that causes rusting of the barrel (though some
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 ...
compounds can leave hygroscopic salts that have a similar effect; non-corrosive primer compounds were introduced in the 1920s).
)
Faster-burning propellants generate higher temperatures and higher pressures, however they also increase wear on gun barrels.
Nitrocellulose deteriorates with time, yielding acidic byproducts. Those byproducts catalyze the further deterioration, increasing its rate. The released heat, in case of bulk storage of the powder, or too large blocks of solid propellant, can cause self-ignition of the material. Single-base nitrocellulose propellants are hygroscopic and most susceptible to degradation; double-base and triple-base propellants tend to deteriorate more slowly.
To neutralize the decomposition products, which could otherwise cause corrosion of metals of the cartridges and gun barrels,
calcium carbonate is added to some formulations.
To prevent buildup of the deterioration products,
stabilizers are added. Diphenylamine is one of the most common stabilizers used. Nitrated analogs of diphenylamine formed in the process of stabilizing decomposing powder are sometimes used as stabilizers themselves.
The stabilizers are added in the amount of 0.5–2% of the total amount of the formulation; higher amounts tend to degrade its ballistic properties. The amount of the stabilizer is depleted with time. Propellants in storage should be periodically tested for the amount of stabilizer remaining,
as its depletion may lead to auto-ignition of the propellant.
Composition
Currently, propellants using
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 ...
(
detonation velocity
Explosive velocity, also known as detonation velocity or velocity of detonation (VoD), is the velocity at which the shock wave front travels through a detonated explosive. Explosive velocities are always faster than the local speed of sound in the ...
,
RE factor
TNT equivalent is a convention for expressing energy, typically used to describe the energy released in an explosion. The is a unit of energy defined by that convention to be , which is the approximate energy released in the detonation of a m ...
1.10) (typically an ether-alcohol colloid of nitrocellulose) as the sole explosive propellant ingredient are described as single-base powder.
Propellants mixtures containing nitrocellulose and
nitroglycerin
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating g ...
(detonation velocity , RE factor 1.54) as explosive propellant ingredients are known as double-base powder. Alternatively
diethylene glycol dinitrate
Diethylene glycol dinitrate (DEGDN) is an explosive nitration, nitrated Alcohol (chemistry), alcohol ester with the formula C4H8N2O7. While chemically similar to numerous other high explosives, pure diethylene glycol dinitrate is difficult to ig ...
(detonation velocity , RE factor 1.17) can be used as a nitroglycerin replacement when reduced flame temperatures without sacrificing chamber pressure are of importance.
Reduction of flame temperature significantly reduces barrel erosion and hence wear.
During the 1930s, ''triple-base propellant'' containing nitrocellulose, nitroglycerin or diethylene glycol dinitrate, and a substantial quantity of
nitroguanidine
Nitroguanidine - sometimes abbreviated NGu - is a colorless, crystalline solid that melts at 257 °C and decomposes at 254 °C. Nitroguanidine is an extremely insensitive but powerful high explosive. Wetting it with > 20 wt.-% water effe ...
(detonation velocity , RE factor 0.95) as explosive propellant ingredients was developed. These "cold propellant" mixtures have reduced flash and flame temperature without sacrificing chamber pressure compared to single- and double-base propellants, albeit at the cost of more smoke. In practice, triple base propellants are reserved mainly for large caliber ammunition such as used in (naval)
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 ...
and
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, which suffer from bore erosion the most. During World War II, it had some use by British artillery. After that war it became the standard propellant in all British large caliber ammunition designs except small-arms. Most western nations, except the United States, followed a similar path.
In the late 20th century new propellant formulations started to appear. These are based on nitroguanidine and high explosives of the
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 ...
type (detonation velocity , RE factor 1.60).
Detonation velocities are of limited value in assessing the reaction rates of nitrocellulose propellants formulated to avoid detonation. Although the slower reaction is often described as burning because of similar gaseous end products at elevated temperatures, the decomposition differs from
combustion
Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combusti ...
in an
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
atmosphere. Conversion of nitrocellulose propellants to high-pressure gas proceeds from the exposed surface to the interior of each solid particle in accordance with
Piobert's law. Studies of solid single- and double-base propellant reactions suggest reaction rate is controlled by
heat transfer
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, ...
through the
temperature gradient
A temperature gradient is a physical quantity that describes in which direction and at what rate the temperature changes the most rapidly around a particular location. The temperature gradient is a dimensional quantity expressed in units of degree ...
across a series of zones or phases as the reaction proceeds from the surface into the solid. The deepest portion of the solid experiencing heat transfer melts and begins phase transition from solid to gas in a ''foam zone''. The gaseous propellant decomposes into simpler molecules in a surrounding ''fizz zone''. Energy is released in a luminous outer ''flame zone'' where the simpler gas molecules react to form conventional combustion products like steam and
carbon monoxide
Carbon monoxide (chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simple ...
.
The ''foam zone'' acts as an insulator slowing the rate of heat transfer from the ''flame zone'' into the unreacted solid. Reaction rates vary with pressure; because the foam allows less effective heat transfer at low pressure, with greater heat transfer as higher pressures compress the gas volume of that foam. Propellants designed for a minimum heat transfer pressure may fail to sustain the ''flame zone'' at lower pressures.
The energetic components used in smokeless propellants include
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 ...
(the most common),
nitroglycerin
Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitrating g ...
,
nitroguanidine
Nitroguanidine - sometimes abbreviated NGu - is a colorless, crystalline solid that melts at 257 °C and decomposes at 254 °C. Nitroguanidine is an extremely insensitive but powerful high explosive. Wetting it with > 20 wt.-% water effe ...
, DINA (bis-nitroxyethylnitramine; diethanolamine dinitrate, DEADN; DHE), Fivonite (2,2,5,5-tetramethylol-cyclopentanone tetranitrate, CyP), DGN (
diethylene glycol dinitrate
Diethylene glycol dinitrate (DEGDN) is an explosive nitration, nitrated Alcohol (chemistry), alcohol ester with the formula C4H8N2O7. While chemically similar to numerous other high explosives, pure diethylene glycol dinitrate is difficult to ig ...
), and acetyl cellulose.
Deterrents (or moderants) are used to slow the burning rate. Deterrents include
centralite
Centralite (empirical formula: C17H20N2O) is a gunshot residue also known as ethyl centralite. Its IUPAC name is 1,3-diethyl-1,3-diphenylurea. Ethyl centralite is insoluble in water, but is soluble in acetone, ethanol and benzene. It is mainly us ...
s (symmetrical diphenyl urea—primarily diethyl or dimethyl),
dibutyl phthalate
Dibutyl phthalate (DBP) is an organic compound which is commonly used as a plasticizer because of its low toxicity and wide liquid range. With the chemical formula C6H4(CO2C4H9)2, it is a colorless oil, although commercial samples are often yell ...
,
dinitrotoluene Dinitrotoluenes could refer to one of the following compounds:
* 2,3-Dinitrotoluene
* 2,4-Dinitrotoluene
* 2,5-Dinitrotoluene
* 2,6-Dinitrotoluene
* 3,4-Dinitrotoluene
* 3,5-Dinitrotoluene
External links
*
{{DEFAULTSORT:Dinitrotoluene ...
(toxic and carcinogenic), akardite (asymmetrical diphenyl urea), ortho-Tolyl urethane, and polyester adipate.
Camphor
Camphor () is a waxy, colorless solid with a strong aroma. It is classified as a terpenoid and a cyclic ketone. It is found in the wood of the camphor laurel ('' Cinnamomum camphora''), a large evergreen tree found in East Asia; and in the k ...
was formerly used but is now obsolete.
Stabilizers prevent or slow down self-decomposition. These include
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 oxidiz ...
,
petroleum jelly
Petroleum jelly, petrolatum, white petrolatum, soft paraffin, or multi-hydrocarbon, CAS number 8009-03-8, is a semi-solid mixture of hydrocarbons (with carbon numbers mainly higher than 25), originally promoted as a topical ointment for its h ...
,
calcium carbonate,
magnesium oxide
Magnesium oxide ( Mg O), or magnesia, is a white hygroscopic solid mineral that occurs naturally as periclase and is a source of magnesium (see also oxide). It has an empirical formula of MgO and consists of a lattice of Mg2+ ions and O2− ions ...
,
sodium bicarbonate
Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda, is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation ( Na+) and a bicarbonate anion ( HCO3−) ...
, and beta-Naphthol methyl ether
Obsolete stabilizers include
amyl alcohol
An amyl alcohol is any of eight alcohols with the formula C5H12O. A mixture of pentyl, amyl alcohols (also called amyl alcohol) can be obtained from fusel alcohol. Amyl alcohol is used as a solvent and in esterification, by which is produced amyl a ...
and
aniline
Aniline is an organic compound with the formula C6 H5 NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine
In organic chemistry, an aromatic amine is an organic compound consisting of an aroma ...
.
Decoppering {{Unreferenced, date=December 2009
Decoppering is the act of removing copper and it is most commonly used in the context of the removal of copper residues from the rifling of gun barrels.
Decoppering agents are frequently added to smokeless powder ...
additives hinder the buildup of copper residues from the gun barrel rifling. These include
tin
Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal.
Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...
metal and compounds (e.g.,
tin dioxide
Tin(IV) oxide, also known as stannic oxide, is the inorganic compound with the formula SnO2. The mineral form of SnO2 is called cassiterite, and this is the main ore of tin. With many other names, this oxide of tin is an important material in tin ...
),
and
bismuth
Bismuth is a chemical element with the Symbol (chemistry), symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental ...
metal and compounds (e.g.,
bismuth trioxide
Bismuth(III) oxide is perhaps the most industrially important compound of bismuth
Bismuth is a chemical element with the symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resem ...
,
bismuth subcarbonate
Bismuth subcarbonate (BiO)2CO3, sometimes written Bi2O2(CO3) is a chemical compound of bismuth containing both oxide and carbonate anions. Bismuth is in the +3 oxidation state. Bismuth subcarbonate occurs naturally as the mineral bismutite. Its ...
,
bismuth nitrate
Bismuth(III) nitrate is a salt composed of bismuth in its cationic +3 oxidation state and nitrate anions. The most common solid form is the pentahydrate. It is used in the synthesis of other bismuth compounds. It is available commercially. It is th ...
,
bismuth antimonide
Bismuth antimonides, Bismuth-antimonys, or Bismuth-antimony alloys, (Bi1−''x''Sb''x'') are binary alloys of bismuth and antimony in various ratios.
Some, in particular Bi0.9Sb0.1, were the first experimentally-observed three-dimensional topologi ...
); the bismuth compounds are favored as copper dissolves in molten bismuth, forming brittle and easily removable alloy.
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 ...
foil and lead compounds have been phased out due to toxicity.
Wear reduction materials including
wax
Waxes are a diverse class of organic compounds that are lipophilic, malleable solids near ambient temperatures. They include higher alkanes and lipids, typically with melting points above about 40 °C (104 °F), melting to giv ...
,
talc
Talc, or talcum, is a Clay minerals, clay mineral, composed of hydrated magnesium silicate with the chemical formula Mg3Si4O10(OH)2. Talc in powdered form, often combined with corn starch, is used as baby powder. This mineral is used as a thi ...
and
titanium dioxide
Titanium dioxide, also known as titanium(IV) oxide or titania , is the inorganic compound with the chemical formula . When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or CI 77891. It is a white solid that is insolubl ...
are added to lower the wear of the gun barrel liners. Large guns use
polyurethane
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethan ...
jackets over the powder bags.
Other additives include
ethyl acetate
Ethyl acetate ( systematically ethyl ethanoate, commonly abbreviated EtOAc, ETAC or EA) is the organic compound with the formula , simplified to . This colorless liquid has a characteristic sweet smell (similar to pear drops) and is used in glues ...
(a solvent for manufacture of spherical powder),
rosin
Rosin (), also called colophony or Greek pitch ( la, links=no, pix graeca), is a solid form of resin obtained from pines and some other plants, mostly conifers, produced by heating fresh liquid resin to vaporize the volatile liquid terpene comp ...
(a surfactant to hold the grain shape of spherical powder) and
graphite
Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large ...
(a
lubricant
A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, t ...
to cover the grains and prevent them from sticking together, and to dissipate
static electricity
Static electricity is an imbalance of electric charges within or on the surface of a material or between materials. The charge remains until it is able to move away by means of an electric current or electrical discharge. Static electricity is na ...
).
Flash reduction
Flash reducers dim
muzzle flash
Muzzle flash is the light — both visible and infrared — created by a muzzle blast, which is caused by the sudden release and expansion of high-temperature, high-pressure gases from the muzzle of a firearm during shooting. Both the blast an ...
, the light emitted in the vicinity of the muzzle by the hot propellant gases and the chemical reactions that follow as the gases mix with the surrounding air. Before projectiles exit, a slight pre-flash may occur from gases leaking past the projectiles. Following muzzle exit, the heat of gases is usually sufficient to emit visible radiation: the primary flash. The gases expand but as they pass through the Mach disc, they are re-compressed to produce an intermediate flash. Hot, combustible gases (e.g. hydrogen and carbon-monoxide) may follow when they mix with oxygen in the surrounding air to produce the secondary flash, the brightest. The secondary flash does not usually occur with small arms.
Nitrocellulose contains insufficient oxygen to completely oxidize its carbon and hydrogen. The oxygen deficit is increased by addition of graphite and organic stabilizers. Products of combustion within the gun barrel include flammable gasses like hydrogen and carbon monoxide. At high temperature, these flammable gasses will ignite when turbulently mixed with atmospheric oxygen beyond the muzzle of the gun. During night engagements, the flash produced by ignition can reveal the location of the gun to enemy forces
and cause temporary night-blindness among the gun crew by photo-bleaching
visual purple.
Flash suppressor
A flash suppressor, also known as a flash guard, flash eliminator, flash hider, or flash cone, is a muzzle device attached to the muzzle of a rifle that reduces its visible signature while firing by cooling or dispersing the burning gases that ...
s are commonly used on small arms to reduce the flash signature, but this approach is not practical for artillery. Artillery muzzle flash up to from the muzzle has been observed, and can be reflected off clouds and be visible for distances up to .
For artillery, the most effective method is a propellant that produces a large proportion of inert nitrogen at relatively low temperatures that dilutes the combustible gases. Triple based propellants are used for this because of the nitrogen in the nitroguanidine.
Flash reducers include
potassium chloride
Potassium chloride (KCl, or potassium salt) is a metal halide salt composed of potassium and chlorine. It is odorless and has a white or colorless vitreous crystal appearance. The solid dissolves readily in water, and its solutions have a salt ...
,
potassium nitrate
Potassium nitrate is a chemical compound with the chemical formula . This alkali metal nitrate salt is also known as Indian saltpetre (large deposits of which were historically mined in India). It is an ionic salt of potassium ions K+ and nitrat ...
,
potassium sulfate
Potassium sulfate (US) or potassium sulphate (UK), also called sulphate of potash (SOP), arcanite, or archaically potash of sulfur, is the inorganic compound with formula K2SO4, a white water-soluble solid. It is commonly used in fertilizers, pro ...
,
and
potassium bitartrate
Potassium bitartrate, also known as potassium hydrogen tartrate, with formula K C4 H5 O6, is a byproduct of winemaking. In cooking, it is known as cream of tartar. It is processed from the potassium acid salt of tartaric acid (a carboxylic ac ...
(potassium hydrogen tartrate: a byproduct of wine production formerly used by French artillery).
Before the use of triple based propellants, the usual method of flash reduction was to add inorganic salts like potassium chloride so their
specific heat capacity
In thermodynamics, the specific heat capacity (symbol ) of a substance is the heat capacity of a sample of the substance divided by the mass of the sample, also sometimes referred to as massic heat capacity. Informally, it is the amount of heat t ...
might reduce the temperature of combustion gasses and their finely divided particulate smoke might block visible wavelengths of
radiant energy
Radiant may refer to:
Computers, software, and video games
* Radiant (software), a content management system
* GtkRadiant, a level editor created by id Software for their games
* Radiant AI, a technology developed by Bethesda Softworks for ''The ...
of combustion.
All flash reducers have a disadvantage: the production of smoke.
Manufacturing
Ammunition powders">handloading powders
Smokeless powder may be
corned into small spherical balls or
extruded
Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex c ...
into cylinders or strips with many cross-sectional shapes (strips with various rectangular proportions, single or multi-hole cylinders, slotted cylinders) using solvents such as ether. These extrusions can be cut into short ("flakes") or long pieces ("cords" many inches long).
Cannon
A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder ...
powder has the largest pieces.
The United States Navy manufactured single-base tubular powder for naval artillery at
Indian Head, Maryland
Indian Head is a town in Charles County, Maryland, United States. The population was 3,894 at the 2020 U.S. Census. It has been the site of a naval base specializing in gun and rocket propellants since 1890. Production of nitrocellulose and smoke ...
, beginning in 1900. Similar procedures were used for United States Army production at
Picatinny Arsenal
The Picatinny Arsenal ( or ) is an American military research and manufacturing facility located on of land in Jefferson and Rockaway Township in Morris County, New Jersey, United States, encompassing Picatinny Lake and Lake Denmark. The Ars ...
beginning in 1907
and for manufacture of smaller grained
Improved Military Rifle (IMR) Improved military rifle propellants are tubular nitrocellulose propellants evolved from World War I through World War II for loading military and commercial ammunition and sold to civilians for reloading rifle ammunition for hunting and target shoot ...
powders after 1914. Short-fiber
cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus ''Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor perce ...
linter was boiled in a solution of
sodium hydroxide
Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions .
Sodium hydroxide is a highly caustic base and alkali ...
to remove vegetable waxes, and then dried before conversion to nitrocellulose by mixing with concentrated
nitric and
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid ( Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen and hydrogen, with the molecular formu ...
s. Nitrocellulose still resembles fibrous cotton at this point in the manufacturing process, and was typically identified as pyrocellulose because it would spontaneously ignite in air until unreacted acid was removed. The term guncotton was also used; although some references identify guncotton as a more extensively nitrated and refined product used in
torpedo
A modern torpedo is an underwater ranged weapon launched above or below the water surface, self-propelled towards a target, and with an explosive warhead designed to detonate either on contact with or in proximity to the target. Historically, su ...
and
mine
Mine, mines, miners or mining may refer to:
Extraction or digging
* Miner, a person engaged in mining or digging
*Mining, extraction of mineral resources from the ground through a mine
Grammar
*Mine, a first-person English possessive pronoun
...
warhead
A warhead is the forward section of a device that contains the explosive agent or toxic (biological, chemical, or nuclear) material that is delivered by a missile, rocket, torpedo, or bomb.
Classification
Types of warheads include:
* Explosiv ...
s prior to use of
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 ...
.
Unreacted acid was removed from pyrocellulose pulp by a multistage draining and water washing process similar to that used in
paper
Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distributed ...
mills during production of chemical
woodpulp
Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops, waste paper, or rags. Mixed with water and other chemical or plant-based additives, pulp is the major raw mate ...
. Pressurized alcohol removed remaining water from drained pyrocellulose prior to mixing with ether and diphenylamine. The mixture was then fed through a press extruding a long tubular cord form to be cut into grains of the desired length.
Alcohol and ether were then evaporated from "green" powder grains to a remaining solvent concentration between 3 percent for rifle powders and 7 percent for large artillery powder grains. Burning rate is inversely proportional to solvent concentration. Grains were coated with electrically conductive graphite to minimize generation of static electricity during subsequent blending. "Lots" containing more than ten tonnes of powder grains were mixed through a tower arrangement of blending hoppers to minimize ballistic differences. Each blended lot was then subjected to testing to determine the correct loading charge for the desired performance.
Military quantities of old smokeless powder were sometimes reworked into new lots of propellants.
Through the 1920s
Fred Olsen
Fredrich Olsen (1891–1986) was a British-born American chemist remembered as the inventor of ball propellant and as a donor or seller to the art antiquities collections of Yale University, the University of Illinois, and the Massachusetts Insti ...
worked at Picatinny Arsenal experimenting with ways to salvage tons of single-base cannon powder manufactured for World War I. Olsen was employed by
Western Cartridge Company
The Western Cartridge Company is an American manufacturer of small arms and ammunition that is based in East Alton, Illinois. Founded in 1898, it was the forerunner of the Olin Corporation, formed in 1944, of which Western is still a subsidiary. ...
in 1929 and developed a process for manufacturing
spherical smokeless powder by 1933.
Reworked powder or washed pyrocellulose can be dissolved in ethyl acetate containing small quantities of desired stabilizers and other additives. The resultant syrup, combined with water and
surfactant
Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming ...
s, can be heated and agitated in a pressurized container until the syrup forms an
emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible (unmixable or unblendable) owing to liquid-liquid phase separation. Emulsions are part of a more general class of two-phase systems of matter called colloids. Althoug ...
of small spherical globules of the desired size. Ethyl acetate distills off as pressure is slowly reduced to leave small spheres of nitrocellulose and additives. The spheres can be subsequently modified by adding nitroglycerine to increase energy, flattening between rollers to a uniform minimum dimension, coating with
phthalate
Phthalates (, ), or phthalate esters, are esters of phthalic acid. They are mainly used as plasticizers, i.e., substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used primarily to soften ...
deterrents to retard ignition, and/or glazing with graphite to improve flow characteristics during blending.
Modern smokeless powder is produced in the United States by
St. Marks Powder
St. Marks Powder is a subsidiary of General Dynamics Ordnance and Tactical Systems manufacturing ball propellant in Crawfordville, Florida. The company is a member of the Sporting Arms and Ammunition Manufacturers' Institute (SAAMI).
History
Larg ...
, Inc. owned by
General Dynamics
General Dynamics Corporation (GD) is an American publicly traded, aerospace and defense corporation headquartered in Reston, Virginia. As of 2020, it was the fifth-largest defense contractor in the world by arms sales, and 5th largest in the Uni ...
.
See also
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Antique firearms
An antique firearm is a term to describe a firearm that was designed and manufactured prior to the beginning of the 20th century. Although the exact definition of what constitutes an "antique firearm" varies between countries, the advent of smo ...
*
Brown-brown
Brown-brown is a purported form of cocaine or amphetamine insufflation mixed with smokeless gunpowder. This powder often contains nitroglycerin, a drug prescribed for heart conditions, which might cause vasodilation, permitting the cocaine or a ...
*
Small arms
A firearm is any type of gun designed to be readily carried and used by an individual. The term is legally defined further in different countries (see Legal definitions).
The first firearms originated in 10th-century China, when bamboo tubes c ...
References
Bibliography
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External links
The Manufacture of Smokeless Powders and their Forensic Analysis: A Brief Review Robert M. Heramb, Bruce R. McCord
Hudson Maxim papers (1851–1925) at
Hagley Museum and Library
The Hagley Museum and Library is a nonprofit educational institution in unincorporated New Castle County, Delaware, near Wilmington. Covering more than along the banks of the Brandywine Creek, the museum and grounds include the first du Pont ...
. Collection includes material relating to Maxim's patent on the process of making smokeless powder.
{{Handloading
Cordite
Explosives
Firearm propellants
Solid fuels
Powders