Closed bolt

Common card · No. 499876

A semi or fully automatic firearm which is said to fire from a closed bolt or closed breech is one where, when ready to fire, a round is in the chamber and the bolt and working parts are forward in battery. When the trigger is pulled, the firing pin or striker fires the round; the action is cycled by the energy of the shot, sending the bolt to the rear, which extracts and ejects the empty cartridge case; and the bolt goes forward, feeding a fresh round from the magazine into the chamber, ready for the next shot.

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