Rolling block

Single-shot firearm action

A rolling-block action is a single-shot firearm action where the sealing of the breech is done with a specially shaped breechblock able to rotate on a pin. The breechblock is shaped like a section of a circle. The breechblock is locked into place by the hammer, therefore preventing the cartridge from moving backward at the moment of firing. By cocking the hammer, the breechblock can be rotated freely to reload the breech of the weapon.

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