Hammer (firearms)

The hammer is a part of a firearm that is used to strike the percussion cap/primer, or a separate firing pin, to ignite the propellant and fire the projectile. It is so called due to the fact that it resembles a hammer in both form and function. The hammer itself is a metal piece that forcefully rotates about a pivot point.

Firearms, initially known as “hand cannons”, first became a viable weapon in 1364 through the advancement of chemical technologies to create a gunpowder efficient enough to launch a projectile at high velocities in a hand-held weapon. The issue quickly arose of how to effectively ignite the gunpowder while maintaining the weapon’s aim at the target. Initially, the problem was solved by using a “slow match”: a chemically treated piece of rope that would stay lit for an extended period of time. The smoldering end of the rope would then be manually brought into contact with the gunpowder through a touch hole in the barrel of the weapon when the user was ready to shoot. It proved difficult for the shooter to both keep the weapon aimed and level as well as ignite the gunpowder with the slow match.

The first step to a true hammer system arose shortly after the introduction of the slow match: the matchlock system, introduced in the early 1400s. It acted as an arm, known as a serpentine, that held the lit slow match. When the trigger was pulled, the arm would swing forward from its cocked state (similar to a hammer) via potential energy stored in a spring and bring the lit slow match into contact with the gunpowder. The weapon could be utilized with increased accuracy, since the shooter could maintain both hands on the weapon.

By 1509, the wheellock system arose to solve some difficulties of the matchlock system, though it was a very expensive system. The wheellock system used a piece of pyrite attached to an arm called a dogshead that would be brought into contact with a metal wheel that rotated when the trigger was pulled. This would, in turn, shower sparks upon the gunpowder and cause the weapon to discharge. The wheellock represented a major advancement, for it removed the need for maintaining a continually lit slow match which could go out or give off the shooter’s location in a time of need.

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Wikipedia