Breechblock (Breech Block)

Breech Block for a Sig Sauer P220

Breech Block for a Sig Sauer P220

Breechblock (Breech Block):

A breechblock (breech block) is the part of a firearm that closes the breech of a weapon at the moment of firing. This prevents the rearward escape of gases. A breechblock must close against the breech for firing but be able to be retracted or otherwise moved for loading or unloading or to remove a spent cartridge.