Percussion cap
[3][4] The invention that made the percussion cap possible using the recently discovered fulminates was patented by the Reverend Alexander John Forsyth of Belhelvie, Aberdeenshire, Scotland, in 1807.
[1] 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.
[5][6] 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.
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.
[1] 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.
"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.
[13] 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.
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.
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.
Caplocks were generally applied to the British military musket (the Brown Bess) in 1842, a quarter of a century after the invention of percussion powder and after an elaborate government test at Woolwich in 1834.
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 needle gun originally fired paper cartridges containing a bullet, powder charge and percussion cap, but by the time of the Franco-Prussian War this had evolved into modern brass ammunition.
[16] 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 cartridges.
For muskets such as the 1853 Enfield and 1861 Springfield, this involved installing a firing pin in place of the nipple, and a trapdoor in the breech to accept the new bullets.
[17][18] 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.
