percussionlock

The percussion lock, also known as a percussion cap lock, is a firearm ignition mechanism that uses a small percussion cap placed on a nipple on the firearm. When struck by the hammer, the cap detonates and sends flame through a vent to ignite the main powder charge in the bore. The lock assembly typically includes a lock plate, a mainspring, a tumbler and sear, a hammer (cock), and the nipple that fits into the barrel.

Operation is straightforward: the hammer is cocked, holding a cap on the nipple. On triggering, the hammer strikes the cap, which detonates and releases a flame into the barrel’s powder charge, firing the gun. This design removed the need for a priming pan and was more reliable in wet conditions than the earlier flintlock systems.

History and usage: The percussion lock was developed in the early 19th century as an improvement over flintlock mechanisms and became widely adopted for muskets, rifles, and pistols during the mid- to late 1800s. It remained common in many muzzle-loading firearms and in some sporting arms until cartridge-based firearms gradually supplanted it in the latter half of the 19th century.

Variants and evolution: The term caplock is often used to describe percussion locks that use a separate percussion cap. With the advent of rimfire and centerfire cartridge ammunition, percussion locks became largely obsolete for new designs, though they continued to be produced for historical reproduction and firearms collections.