The lock of a muzzle-loading firearm is the system used to ignite the propellant. Types of lock include matchlock, wheellock, snaplock, doglock, snaphance, flintlock, modern percussion, rotating bolt, and experimental electronic types. Parts of the lock can include the wheel (for wheellocks) and the hammer and frizzen (for flintlocks). A complete muzzleloader consists of lock, stock, and barrel. In breech-loading weapons, the general mechanism for handling ammunition is known as the firearm action.