Firearm actions

In firearms terminology, an action is the mechanism that handles the ammunition (loads, locks, fires, and extracts the cartridges) or the method by which that mechanism works. Breech-loading weapons have actions; actions are technically not present on muzzleloaders, as all loading is done by hand. The mechanism that fires a muzzle-loader is called the lock.

Actions can be categorized in several ways, including single action versus double action, break action versus bolt action, and others. The term action can also include short, long, and magnum if it is in reference to the length of the rifle’s receiver and the length of the bolt. The short action rifle usually can accommodate a cartridge length of 2.8 in (71 mm) or smaller. The long action rifle can accommodate a cartridge of 3.34 in (85 mm), and the magnum action rifle can accommodate cartridges of 3.6 in (91 mm), or longer in length.

Manual operation is a firearms term describing any type of firearm action that is loaded one shot at a time by the user rather than automatically. For example, break action is a form of manual operation using a simple hinge mechanism that is manually unlatched by the operator, exposing the chamber(s) for reloading.

Dropping black are actions wherein the breechblock lowers or "drops" into the receiver to open the breech, usually actuated by an underlever. There are two principal types of dropping block: the tilting block and the falling block.

In a tilting block or pivoting block action, the breechblock is hinged on a pin mounted at the rear. When the lever is operated, the block tilts down and forward, exposing the chamber. The best-known pivoting block designs are the Peabody, the Peabody–Martini, and Ballard actions.

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