Extractor (firearms)

An extractor is a part in a firearm that serves to remove brass cases of fired ammunition after the ammunition has been fired. When the gun's action cycles, the extractor lifts or removes the spent brass casing from the firing chamber.

Extractors can be found on bolt-action, lever-action, pump-action, semi-automatic and fully automatic firearms. Break-action shotguns and double rifles, such as those with single or double barrels, typically have an extractor that operates when the action is broken open. Extractors are also found on revolvers, removing cases either in succession (as in a fixed-cylinder single-action revolver) or simultaneously (as in a double-action revolver with a swing-out and top-break cylinder). For rimless cases, an extractor groove in the ammunition may serve as the point from which the extractor works. For rimmed cases, the rim of the cartridge most commonly serves as the point from which the extractor works. Not all firearms have extractors.

In bolt-action, lever-action, pump-action, and semi- or fully automatic firearms, extractors typically work in conjunction with ejectors to remove completely a fired, empty cartridge case from the weapon. The extractor removes the cartridge case from the chamber, essentially pulling the case to the rear. At some point in the rearward travel, the case typically makes contact with the ejector, which "kicks" the expended case out of the firearm, making room for an unfired cartridge to be loaded.

Some firearms have no ejectors, only extractors, requiring the user to manually remove spent cartridges. In this situation, the extractor pulls the case out of the chamber far enough to give the user a good grip on the cartridge, but not far enough to remove the entire cartridge from the chamber. This situation is encountered on some single-shot rifles, single-shot pistols such as the Thompson Contender with its break-action design, and on some break-action single- and double-barrel shotguns.

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