The percussion cap, percussion primer, or caplock, introduced in the early 1820s, is a type of single-use percussion ignition device for muzzle loader firearm locks enabling them to fire reliably in any weather condition. Its invention gave rise to the caplock mechanism or percussion lock system which used percussion caps struck by the

hammer A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nail (fastener), nails into wood, to sh ...

to set off 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, charcoal (which is mostly carbon), and potassium nitrate, potassium ni ...

charge in rifles and cap and ball

firearm A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and operated by an individual. The term is legally defined further in different countries (see legal definitions). The first firearms originate ...

s. Any firearm using a caplock mechanism is a percussion gun. Any

long gun A long gun is a category of firearms with long Gun barrel, barrels. In small arms, a ''long gun'' or longarm is generally designed to be held by both hands and braced against the shoulder, in contrast to a handgun, which can be fired being held w ...

with a cap-lock mechanism and rifled

barrel A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden stave (wood), staves and bound by wooden or metal hoops. The word vat is often used for large containers ...

is a percussion rifle. Cap and ball describes cap-lock firearms discharging a single bore-diameter

spherical A sphere (from Ancient Greek, Greek , ) is a surface (mathematics), surface analogous to the circle, a curve. In solid geometry, a sphere is the Locus (mathematics), set of points that are all at the same distance from a given point in three ...

bullet A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. They are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax; and are made in various shapes and constru ...

with each shot.

Description

The percussion cap is a small cylinder of

copper Copper is a chemical element; it has symbol Cu (from Latin ) 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 pinkish-orang ...

brass Brass is an alloy of copper and zinc, in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic and chemical properties, but copper typically has the larger proportion, generally copper and zinc. I ...

with one closed end. Inside the closed end is a small amount of a shock-sensitive explosive material such as

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 ...

(discovered in 1800; it was the only practical detonator used from about the mid-19th century to the early 20th century). The caplock mechanism consists of a

and a ''nipple'' (sometimes referred to as a ''cone''). The nipple contains a hollow

conduit Conduit may refer to: Engineering systems * Conduit (fluid conveyance), a pipe suitable for carrying either open-channel or pressurized liquids * Electrical conduit, a protective cover, tube or piping system for electric cables * Conduit cur ...

which goes into the rearmost part of the gun barrel, and the percussion cap is placed over the nipple hole. Pulling the trigger releases the hammer, which strikes the percussion cap against the nipple (which serves as an

anvil An anvil is a metalworking tool consisting of a large block of metal (usually Forging, forged or Steel casting, cast steel), with a flattened top surface, upon which another object is struck (or "worked"). Anvils are massive because the hi ...

), crushes it and detonates the mercury fulminate inside, which releases sparks that travel through the hollow nipple into the barrel and ignite the main powder charge. Percussion caps have been made in small sizes for pistols and larger sizes for rifles and muskets.

Origins

Earlier firearms used

flintlock Flintlock is a general term for any firearm that uses a flint-striking lock (firearm), ignition mechanism, the first of which appeared in Western Europe in the early 16th century. The term may also apply to a particular form of the mechanism its ...

mechanism Mechanism may refer to: *Mechanism (economics), a set of rules for a game designed to achieve a certain outcome **Mechanism design, the study of such mechanisms *Mechanism (engineering), rigid bodies connected by joints in order to accomplish a ...

s causing a piece of

flint Flint, occasionally flintstone, is a sedimentary cryptocrystalline form of the mineral quartz, categorized as the variety of chert that occurs in chalk or marly limestone. Historically, flint was widely used to make stone tools and start ...

to strike a

steel Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...

frizzen The frizzen, historically called the "hammer" or the steel,This may appear anomalous since, in later firearm designs (e.g. percussion locks), the component operating in the same manner as the ''cock'' is called the hammer. is an L-shaped piece of ...

producing sparks to ignite a pan of priming powder and thereby fire the gun's main powder charge. The flintlock mechanism replaced older ignition systems such as the

matchlock A matchlock or firelock is a historical type of firearm wherein the gunpowder is ignited by a burning piece of flammable cord or twine that is in contact with the gunpowder through a mechanism that the musketeer activates by pulling a lever or Tri ...

and

wheellock A wheellock, wheel-lock, or wheel lock is a friction-wheel mechanism which creates a spark that causes a firearm to fire. It was the next major development in firearms technology after the matchlock, and the first self-igniting firearm. Its name ...

, but all were prone to misfire in wet weather. The discovery of

fulminate Fulminates are chemical compounds which include the fulminate ion (). The fulminate ion is a pseudohalic ion because its charge and reactivity are similar to those of the halogens. The name is derived from the Latin ''fulminātus'', meaning to ...

s was made by

Edward Charles Howard Edward Charles Howard FRS (28 May 1774 – 28 September 1816) the youngest brother of Bernard Howard, 12th Duke of Norfolk, was a British chemist who has been described as "the first chemical engineer of any eminence." Career In January 1799 ...

(1774–1816) in 1800. The invention that made the percussion cap possible using the recently discovered fulminates was patented by the

Reverend The Reverend (abbreviated as The Revd, The Rev'd or The Rev) is an honorific style (form of address), style given to certain (primarily Western Christian, Western) Christian clergy and Christian minister, ministers. There are sometimes differen ...

Alexander John 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 pe ...

Belhelvie Belhelvie () is a small village and civil parish in Aberdeenshire in Scotland.Belhelvie.

, Aberdeenshire, Scotland, in 1807. The rudimentary percussion system was invented by Forsyth as a solution to the problem that birds would startle when smoke puffed from the powder pan of his flintlock shotgun, giving them sufficient warning to escape the shot. This early percussion lock system operated in a nearly identical fashion to flintlock firearms and used a fulminating primer made of fulminate of mercury, chlorate of potash,

sulphur Sulfur (American spelling and the preferred IUPAC name) or sulphur (English in the Commonwealth of Nations, Commonwealth spelling) is a chemical element; it has Symbol (chemistry), symbol S and atomic number 16. It is abundance of the chemical ...

and

charcoal Charcoal is a lightweight black carbon residue produced by strongly heating wood (or other animal and plant materials) in minimal oxygen to remove all water and volatile constituents. In the traditional version of this pyrolysis process, ca ...

, ignited by concussion. His invention of a fulminate-primed firing mechanism deprived the birds of their early warning system, both by avoiding the initial puff of smoke from the flintlock powder pan, as well as shortening the interval between the trigger pull and the shot leaving the muzzle. Forsyth patented his "scent bottle" ignition system in 1807. However, it was not until after Forsyth's patents expired that the conventional percussion cap system was developed. Joseph Manton invented a precursor to the percussion cap in 1814, comprising a copper tube that detonated when crushed. This was further developed in 1822 by the English-born American artist Joshua Shaw, as a copper cup filled with fulminates. The first purpose-built caplock guns were

fowling piece A shotgun (also known as a scattergun, peppergun, or historically as a fowling piece) is a long-barreled firearm designed to shoot a straight-walled cartridge known as a shotshell, which discharges numerous small spherical projectiles called ...

s commissioned by sportsmen in

Regency era The Regency era of British history is commonly understood as the years between and 1837, although the official regency for which it is named only spanned the years 1811 to 1820. King George III first suffered debilitating illness in the lat ...

England. Due to the mechanism's compactness and superior reliability compared to the flintlock, gunsmiths were able to manufacture pistols and long guns with two barrels. Early caplock handguns with two or more barrels and a single lock are known as turn-over or twister pistols, due to the need to manually rotate the second barrel to align with the hammer. With the addition of a third barrel, and a ratchet to mechanically turn the barrels while cocking the hammer, these caplock pistols evolved into the

pepper-box The pepper-box pistol or simply pepperbox (also "pepper-pot", from its resemblance to the household pepper shakers) is a multiple-barrel firearm, mostly in the form of a handgun, that has three or more gun barrels each holding a single shot. ...

revolver A revolver is a repeating handgun with at least one barrel and a revolving cylinder containing multiple chambers (each holding a single cartridge) for firing. Because most revolver models hold six cartridges before needing to be reloaded, ...

during the 1830s. The caplock offered many improvements over the flintlock. The caplock was easier and quicker to load, more resilient to weather conditions, and far more reliable than the flintlock. Many of the older flintlock weapons were later converted to the caplock, so that they could take advantage of these features. File:Japanese 19th century percussion pistol 1.jpg, Japanese

samurai The samurai () were members of the warrior class in Japan. They were originally provincial warriors who came from wealthy landowning families who could afford to train their men to be mounted archers. In the 8th century AD, the imperial court d ...

's matchlock converted to caplock File:Pair of Four-Barreled Turnover Percussion Pistols with Pair of Box-Lock Turn-Off Pocket Pistols, Case, and Accessories MET DP-13844-009.jpg, A pair of caplock twister pistols File:Pistolet à percussion inversée IMG 3074.jpg, Inverted percussion pistol, 9.5 mm; made by gunsmith Correvon,

Morges Morges (; , Plurale tantum, plural, probably Ablative (Latin), ablative, else dative; ) is a Municipalities of Switzerland, municipality in the Switzerland, Swiss Cantons of Switzerland, canton of Vaud and the seat of the Morges District, distri ...

, 1854 File:Booth deringer.jpg,

John Wilkes Booth John Wilkes Booth (May 10, 1838April 26, 1865) was an American stage actor who Assassination of Abraham Lincoln, assassinated United States president Abraham Lincoln at Ford's Theatre in Washington, D.C., on April 14, 1865. A member of the p ...

's single-shot caplock

derringer A derringer or deringer is a small handgun that is neither a revolver, semi-automatic pistol, nor machine pistol. It is not to be confused with mini-revolvers or pocket pistols, although some later derringers were manufactured with the pepp ...

used to assassinate

Abraham Lincoln Abraham Lincoln (February 12, 1809 – April 15, 1865) was the 16th president of the United States, serving from 1861 until Assassination of Abraham Lincoln, his assassination in 1865. He led the United States through the American Civil War ...

Parallel developments

Joshua Shaw is sometimes credited (primarily by himself) with the development of the first metallic percussion cap in 1814, a reusable one made of iron, then a disposable pewter one in 1815 and finally a copper one in 1816. There is no independent proof of this since Shaw was advised he could not patent it due to Alexander Forsyth's patent for using fulminates to ignite guns being in force between 1807 and 1821. Shaw says he only shared the development of his innovation with a few associates (gunmakers and others) who were sworn to secrecy and never provided affidavits at a later date. Shaw's claim to have been the inventor remains clouded in controversy as he did not patent the idea until 1822, having moved to America in 1817. According to Lewis Winant, the US government's decision to award Shaw $25,000 as compensation for his invention being used by the Army was a mistake. Congress believed Shaw's patent was the earliest in the world and awarded him a large sum of money based on this belief. The investigators had overlooked two French patents and the earlier use of the idea in Britain. The earliest known patent anywhere in the world which specifically mentions a percussion cap and nipple was granted in France on 29 July 1818 to

François Prélat François Prélat was a Frenchman involved in gunmaking in the early part of the nineteenth century. It is sometimes claimed that he invented the first fully contained cartridge in 1808, as well as the percussion cap in 1818. However most gun hist ...

, four years before Shaw's patent. Prelat made a habit of copying English patents and inventions and the mode of operation he describes is flawed. Secondly a French patent of a percussion cap and nipple had been granted in 1820 to Deboubert. However predating both of these French claims, the most likely inventor of the percussion cap, according to historian Sidney James Gooding, was Joseph Egg (nephew of Durs Egg), around 1817, . There were other earlier claims. Col.

Peter Hawker Colonel Peter Hawker (24 November 1786 – 7 August 1853) was a celebrated diarist and author, and a shooting sportsman accounted one of the "great shots" of the 19th century. His sporting exploits were widely followed and on occasion consider ...

in 1830 simultaneously claimed and denied being the inventor. "I do not wish to say I was the inventor of it - very probably not" but then immediately recounts that he came up with the idea of simplifying a Manton patch-lock, which could be troublesome, by designing a cap and nipple arrangement around 1816 when the patch lock was patented. He says he then presented a drawing to a reluctant Joseph Manton to make a few copper cap guns which were then sold. Hawker, seems to give Joseph Manton more of the glory eight years later in the 1838 edition of his 'Instructions to young Sportsmen', by stating categorically that "copper tubes and primers were decidedly invented by Joe Manton". By the 1850s Hawker was again claiming the invention for himself in his press advertisements. Despite many years of research by Winant, Gooding and De Witt Bailey, the jury is still out as the competing claims are based on personal accounts and have little or no independently verifiable evidence. While the metal percussion cap was the most popular and widely used type of primer, their small size made them difficult to handle under the stress of combat or while riding a horse. Accordingly, several manufacturers developed alternative, "auto-priming" systems. The " Maynard tape primer", for example, used a roll of paper "caps" much like today's toy cap gun. The Maynard tape primer was fitted to some firearms used in the mid-nineteenth century and a few saw brief use in the

American Civil War The American Civil War (April 12, 1861May 26, 1865; also known by Names of the American Civil War, other names) was a civil war in the United States between the Union (American Civil War), Union ("the North") and the Confederate States of A ...

. Other disc or pellet-type primers held a supply of tiny fulminate detonator discs in a small magazine. Cocking the hammer automatically advanced a disc into position. However, these automatic feed systems were difficult to make with the manufacturing systems in the early and mid-nineteenth century and generated more problems than they solved. They were quickly shelved in favor of a single percussion cap that, while unwieldy in some conditions, could be carried in sufficient quantities to make up for occasionally dropping one, while a jammed tape primer system would instead reduce the rifle to an awkward club.

Military firearms

This invention was gradually improved, and came to be used, first in a steel cap and then in a copper cap, by various gunmakers and private individuals before coming into general military use nearly thirty years later. The alteration of the military flintlock to the percussion musket was easily accomplished by replacing the powder pan and steel frizzen with a nipple and by replacing the cock or hammer that held the flint by a smaller hammer formed with a hollow made to fit around the nipple when released by the trigger. On the nipple was placed the copper cap containing Shaw's detonating composition of three parts of chlorate of potash, two of fulminate of mercury and one of powdered glass. The hollow in the hammer contained the fragments of the cap if it fragmented, reducing the risk of injury to the firer's eyes. From the 1820s onwards, the armies of Britain, France, Russia, and America began converting their muskets to the new percussion system. Caplocks were generally applied to the British military musket (the

Brown Bess "Brown Bess" is a nickname of uncertain origin for the British Army's Muzzleloader, muzzle-loading smoothbore flintlock Land Pattern Musket and its derivatives. The musket design remained in use for over a hundred years with many incremental c ...

) in 1842, a quarter of a century after the invention of percussion powder and after an elaborate government test at Woolwich in 1834. The first percussion firearm produced for the US military was the percussion carbine version (c.1833) of the

M1819 Hall rifle The M1819 Hall rifle was a single-shot breech-loading rifle (also considered something of a hybrid breech and muzzle-loading design) designed by John Hancock Hall, patented on May 21, 1811, and adopted by the U.S. Army in 1819. It was preceded b ...

. The Americans'

breech loading 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 leave ...

caplock Hall rifles, muzzle loading rifled muskets and Colt Dragoon

s gave them an advantage over the

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. Some examples of smoothbore weapons are muskets, blunderbusses, and flintlock pistols. ...

flintlock Brown Bess muskets used by Santa Anna's troops during the Mexican War. In Japan, matchlock pistols and muskets were converted to percussion from the 1850s onwards, and new guns based on existing designs were manufactured as caplocks. The Austrians instead used a variant of Manton's tube lock in their

Augustin musket The Augustin musket was an Austrian musket used in the mid 19th century. It was used in several European wars, and also featured in the U.S. Civil War. History The Augustin Infantry Musket was an Austrian musket that was manufactured from 1842 to ...

until the conventional caplock

Lorenz rifle The Lorenz rifle was an Austrian rifle used in the mid 19th century. It was used in the Second Italian War of Independence in 1859 and the Austro-Prussian War in 1866, and also featured prominently in the American Civil War. History The Lorenz r ...

was introduced in 1855. The first practical solution for the problem of handling percussion caps in battle was the Prussian 1841 (

Dreyse needle gun Dreyse may refer to: * Johann Nicolaus von Dreyse (1787–1867), German firearms inventor * Hitch Dreyse, a fictional List of Attack on Titan characters, character in ''Attack on Titan'' (''Shingeki no Kyojin'') series who serves in the military po ...

), which used a long needle to penetrate a paper cartridge filled with black powder and strike the percussion cap that was fastened to the base of the bullet. While it had a number of problems, it was widely used by the Prussians and other German states in the mid-nineteenth century and was a major factor in the 1866

Austro-Prussian War The Austro-Prussian War (German: ''Preußisch-Österreichischer Krieg''), also known by many other names,Seven Weeks' War, German Civil War, Second War of Unification, Brothers War or Fraternal War, known in Germany as ("German War"), ''Deutsc ...

. The needle gun originally fired paper cartridges containing a bullet, powder charge and percussion cap, but by the time of the

Franco-Prussian War The Franco-Prussian War or Franco-German War, often referred to in France as the War of 1870, was a conflict between the Second French Empire and the North German Confederation led by the Kingdom of Prussia. Lasting from 19 July 1870 to 28 Janua ...

this had evolved into modern brass ammunition. File:Rifled musket actions.jpg, Reproduction Springfield and Enfield caplocks File:Pistol img 3011.jpg, Detail of the firing mechanism on an instruction cutaway model of a French navy percussion pistol, model 1837 File:Pistole 1842.jpg, Caplock horse pistol, Swiss Ordnance 1817/42 File:Loadseq.jpg, Loading sequence for percussion revolvers

Later firearms evolution

The percussion cap brought about the invention of the modern cartridge case and made possible the general adoption of the breech-loading principle for all varieties of rifles, shotguns and pistols. After the American Civil War, Britain, France, and America began converting existing caplock guns to accept brass rimfire and

centrefire Two rounds of .357 Magnum, a centerfire cartridge; notice the circular primer in the center A center-fire (or centerfire) is a type of metallic cartridge used in firearms, where the primer is located at the center of the base of its casing (i ...

cartridges. For muskets such as the 1853 Enfield and 1861 Springfield, this involved installing a

firing pin A firing pin or striker is a part of the firing mechanism of a firearm that impacts the primer in the base of a cartridge and causes it to fire. In firearms terminology, a striker is a particular type of firing pin where a compressed sprin ...

in place of the nipple, and a trapdoor in the breech to accept the new bullets. Examples include the Trapdoor Springfield, Tabatière rifle, Westley Richards and

Snider–Enfield The British .577 Snider–Enfield was a breechloader, breech-loading rifle. The American inventor, Jacob Snider created this action (firearms), firearm action, and the Snider–Enfield was one of the most widely used of the Snider varieties. The ...

conversions. The British Army used Snider Enfields contemporaneously with the

Martini–Henry The Martini–Henry is a breech-loading single-shot rifle with a lever action that was used by the British Army. It first entered service in 1871, eventually replacing the Snider–Enfield, a muzzle-loader converted to the cartridge system. Mar ...

rifle until the .303

bolt action Bolt action is a type of manual firearm action that is operated by ''directly'' manipulating the turn-bolt via a bolt handle, most commonly placed on the right-hand side of the firearm (as most users are right-handed). The majority of b ...

Lee–Metford The Lee–Metford (also known as the Magazine Lee–Metford) is a British bolt action rifle which combined James Paris Lee's rear-locking bolt system and detachable magazine with an innovative seven-groove rifled barrel designed by William Ell ...

repeating rifle A repeating rifle is a single-barreled rifle capable of repeated discharges between each ammunition reload. This is typically achieved by having multiple cartridges stored in a magazine (within or attached to the rifle) and then fed individually ...

was introduced in the 1880s. Later,

military surplus Military surplus is goods, usually materiel, that are sold or otherwise disposed of when held in excess or are no longer needed by the military. Entrepreneurs often buy these goods and resell them at surplus stores. Usually the goods sold by th ...

Sniders were purchased as hunting and defensive weapons by British colonists and trusted local natives. Caplock revolvers such as the Colt Navy and Remington were also widely converted during the late 19th century, by replacing the existing cylinder with one designed for modern ammunition. These were used extensively by the Turks in the

Russo-Turkish War The Russo-Turkish wars ( ), or the Russo-Ottoman wars (), began in 1568 and continued intermittently until 1918. They consisted of twelve conflicts in total, making them one of the longest series of wars in the history of Europe. All but four of ...

, the

US Cavalry The United States Cavalry, or U.S. Cavalry, was the designation of the mounted force of the United States Army. The United States Cavalry was formally created by an act of United States Congress, Congress on 3 August 1861 and ceased as a dist ...

during the

Indian Wars The American Indian Wars, also known as the American Frontier Wars, and the Indian Wars, was a conflict initially fought by European colonial empires, the United States, and briefly the Confederate States of America and Republic of Texas agains ...

, and also by

gunfighter Gunfighters, also called gunslingers () or in the late 19th and early 20th century gunmen, were individuals in the American Old West who gained a reputation of being dangerous with a gun and participated in shootouts. Today, the term "gunslin ...

s, lawmen, and outlaws in the old west. In the 1840s and 1850s, the percussion cap was first integrated into a metallic cartridge, where the bullet is held in by the casing, the casing is filled with gunpowder, and a primer is placed on the end. By the 1860s and 1870s,

breech-loading A breechloader is a firearm in which the user loads the ammunition from the breech end of the barrel (i.e., from the rearward, open end of the gun's barrel), as opposed to a muzzleloader, in which the user loads the ammunition from the ( muzzle ...

metallic cartridges had made the percussion cap system obsolete. Today, reproduction percussion firearms are popular for recreational shooters and percussion caps are still available (though some modern muzzleloaders use shotshell primers instead of caps). Most percussion caps now use non-corrosive compounds such as

lead styphnate Lead styphnate (lead 2,4,6- trinitroresorcinate, C6HN3O8Pb ), whose name is derived from styphnic acid, is an explosive used as a component in primer and detonator mixtures for less sensitive secondary explosives. Lead styphnate is only slight ...

Other uses

Caps are used in cartridges,

grenade A grenade is a small explosive weapon typically thrown by hand (also called hand grenade), but can also refer to a Shell (projectile), shell (explosive projectile) shot from the muzzle of a rifle (as a rifle grenade) or a grenade launcher. A mod ...

rocket-propelled grenade A rocket-propelled grenade (RPG), also known colloquially as a rocket launcher, is a Shoulder-fired missile, shoulder-fired anti-tank weapon that launches rockets equipped with a Shaped charge, shaped-charge explosive warhead. Most RPGs can ...

s and rescue flares. Percussion caps are also used in

land mine A land mine, or landmine, is an explosive weapon often concealed under or camouflaged on the ground, and designed to destroy or disable enemy targets as they pass over or near it. Land mines are divided into two types: anti-tank mines, wh ...

fuze In military munitions, a fuze (sometimes fuse) is the part of the device that initiates its function. In some applications, such as torpedoes, a fuze may be identified by function as the exploder. The relative complexity of even the earliest fu ...

booby-trap A booby trap is a device or setup that is intended to kill, harm or surprise a human or an animal. It is triggered by the presence or actions of the victim and sometimes has some form of bait designed to lure the victim towards it. The trap may b ...

firing devices and

anti-handling device An anti-handling device is an attachment to or an integral part of a landmine or other munition such as some fuze types found in general-purpose air-dropped bombs, cluster bombs and sea mines. It is designed to prevent tampering or disabling, ...

s. Most purpose-made military booby-trap firing devices contain some form of

spring-loaded A spring is a device consisting of an elastic but largely rigid material (typically metal) bent or molded into a form (especially a coil) that can return into shape after being compressed or extended. Springs can store energy when compresse ...

designed to strike a percussion cap connected to a

detonator A detonator is a device used to make an explosive or explosive device explode. Detonators come in a variety of types, depending on how they are initiated (chemically, mechanically, or electrically) and details of their inner working, which of ...

at one end. The detonator is inserted into an explosive charge—e.g., C-4 or a block of

TNT Troponin T (shortened TnT or TropT) is a part of the troponin complex, which are proteins integral to the contraction of skeletal and heart muscles. They are expressed in skeletal and cardiac myocytes. Troponin T binds to tropomyosin and helps ...

. Triggering the booby-trap (e.g., by pulling on a trip-wire) releases the cocked firing pin that flips forward to strike the percussion cap, firing it and the attached detonator; the shock-wave from the detonator sets off the main explosive charge. Image:Russian - VPF pull fuze.jpg,

USSR The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

booby trap firing device – pull

: normally connected to a

tripwire A tripwire is a passive triggering mechanism. Typically, a wire or cord is attached to a device for detecting or reacting to physical movement. Military applications Such tripwires may be attached to one or more mines⁠especially fragme ...

. Percussion cap is clearly labelled. Image:Russian - MUV pull fuze.jpg, Alternative design of USSR booby trap firing device – pull fuze: normally connected to tripwire. Percussion cap is clearly labelled. Image:Russian MV-5 pressure fuze.jpg, USSR boobytrap firing device – pressure fuze: victim steps on loose floorboard with fuze concealed underneath. Image:Type_99_grenade.jpg, Cross-sectional view of a Japanese Type 99 grenade showing percussion primer Image:smine-sensor.jpg, Cross-sectional view of the fuze fitted to a German

S-mine The German S-mine (''Schrapnellmine'', ''Springmine'' or ''Splittermine'' in German), known by enemy Allied Forces as the "Bouncing Betty" on the Western Front and "frog-mine" on the Eastern Front, is the best-known version of a class of mines ...

. Percussion cap is clearly labelled.

Citations

Bibliography

* Winant, L. (1956). ''Early percussion firearms''. Bonanza Books

External links

How percussion caps work
{{Firearms 19th-century inventions Ammunition Detonators Early modern firearms Firearm actions Mechanisms (engineering) Scottish inventions