Gun Wiki
Striker redirects here. For the shotgun, see Striker shotgun.

An AR-15 firing pin.

The firing pin is the part that pierces the primer on a cartridge once the hammer is released. It may float freely in its channel (usually within the bolt) or be spring-loaded. Firing pins may also be on the hammer if the weapon is a revolver, as revolvers do not have bolts or striker assemblies.

Rimfire firing pin

Rimfire firing pins are usually made from flat sheet steel, some cases round at the front.

Fixed firing pin

Fixed firing pins have the pin in the fixed position in the bolt/bolt carrier or machined in the bolt face. This type is common in open bolt firearms such as machine guns, submachine guns etc.

Free floating firing pin

Floating firing pins are found in the bolt/bolt carrier and only move when the firearm is operated.


A striker assembly.

A striker is a firing pin attached directly to a spring, which provides the tension necessary for the pin to pierce the primer. Striker-fired weapons do not need hammers, as the striker assembly combines both the hammer and firing pin function into one part.