Pinfire

A pinfire cartridge is an obsolete type of metallic firearm cartridge in which the priming compound is ignited by striking a small pin which protrudes radially from just above the base of the cartridge. Invented by Frenchman Casimir Lefaucheux in the 1830s but not patented until 1835, it was one of the earliest practical designs of a metallic cartridge. Its history is closely associated with the development of the breechloader which replaced muzzle-loading weapons.

The Swiss gun maker Samuel Joannes Pauly patented the first breechloading cartridge in 1812. This was for use in a shotgun with fixed barrels which was loaded by lifting a breech block on the top. French gun maker Henri Roux attempted to improve this cartridge in the 1820s but a constantly primed cartridge was felt by many to be too dangerous and many breechloading guns reverted to using an unprimed cartridge. This was fired by a separate percussion cap which was used on the still dominant muzzle-loading guns.

Casimir Lefaucheux of Paris decided in 1832 to patent a breechloader where the barrel hinged downwards to reveal the breech ends. These still used a separate percussion cap. Though used before this, (as seen in surviving pinfire shotshells that lists the names of early gun makers he signed contracts with in 1833 and 1834,) in 1835 he was granted an addition to the 1832 patent for a new type of cartridge in which the cartridge's priming compound is ignited by striking a small pin which protrudes radially from just above the base of the cartridge. These pins fitted into a small groove cut in the top of each barrel-end and made it easy to see if the gun was loaded. The cartridge used metal bases (often brass) with paper tubes which were usually loaded by the shooter or his staff but were not entirely gas-tight. This reduced the force of the charge and allowed powder residue and gas to escape.

The pinfire cartridge was greatly improved by the 1846 patent (number 1963) by Benjamin Houllier of Paris which introduced a base wad and effectively made the cartridge gas-tight which greatly improved the performance. They were cheap and clean shooting. These improved pinfire guns grew in popularity in France and some were imported by British gun makers to overwhelming indifference on the part of the gun users there. They were prejudiced technically against a gun that 'broke' in the middle, despite the much vaunted benefits of breechloading. They owned muzzle-loaders of exquisite perfection, considered themselves the best engineers in the world (inventing the Industrial Revolution), and had a poor view of the French - the old enemy and an unreliable ally.

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