Flintlock mechanism

The flintlock mechanism is a type of lock used on muskets, pistols, and rifles in the 17th, 18th, and 19th centuries. It is commonly referred to as a "flintlock" (without the word mechanism), though that term is also commonly used for the weapons themselves as a whole, and not just the lock mechanism.

The flintlock, also known as the true flintlock, was developed in France in the early 17th century. It quickly replaced earlier technologies, such as the matchlock and wheellock and the earlier flintlocks. It continued to be in common use for over two centuries, until it was finally replaced by the percussion lock.

Flintlock firing mechanisms made their appearance in the 16th century in the form of the snaplock, the snaphance, the miquelet, and the doglock. The so-called true flintlock was developed in France in the early 17th century. Though its exact origins are not known, credit for the development of the true flintlock is usually given to Marin le Bourgeoys, an artist, gunsmith, luthier, and inventor from Normandy, France. Marin le Bourgeoys's basic design became the standard for flintlocks, quickly replacing most older firing mechanisms throughout Europe. Flintlock weapons based on this design were used for over two centuries, until gradually superseded by caplock mechanisms in the early 19th century.

The key element apparently added by Marin le Bourgeoys was the vertically acting sear. The sear is a "catch" or "latch" which holds the mechanism in a position ready to fire; the trigger acts upon, or is part of, the sear, releasing it and allowing a strong spring to act on the mechanism to fire the gun. Previously the sear, located within the lock, had acted through a hole in the lockplate to engage the cock on the outside of the plate. The vertically acting sear acted on a piece called the tumbler, on the inside of the lock which was mounted on the same rotating shaft as the cock. This design proved to be the most efficient in terms of cost and reliability.

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