Semiautomatic firearm

A semi-automatic, or self-loading firearm, is one that not only fires a bullet each time the trigger is pulled, but also performs all steps necessary to prepare it to discharge again—assuming cartridges remain in the firearm's feed device. Typically, this includes extracting and ejecting the spent cartridge case from the firing chamber, re-cocking the firing mechanism, and loading a new cartridge into the firing chamber. To fire again, the trigger is released and re-pressed.

Ferdinand Ritter von Mannlicher produced the first successful design for a semi-automatic rifle in 1885, and by the early 20th century, many manufacturers had introduced semi-automatic shotguns, rifles and pistols.

In military use, self-loading rifles were barely used in World War I, and most armies in World War II also still relied upon bolt-action rifles, with the exception of the Americans, who in 1937 had adopted the M1 Garand as the standard-issue infantry weapon.

The first successful design for a semi-automatic rifle is attributed to German-born gunsmith Ferdinand Ritter von Mannlicher, who unveiled the design in 1885. The Model 85 was followed by the equally innovative Mannlicher Models 91, 93 and 95 semi-automatic rifles. Although Mannlicher earned his reputation with his bolt-action rifle designs, he also produced a few semi-automatic pistols, including the Steyr Mannlicher M1894, which employed an unusual blow-forward action and held five rounds of 6.5 mm ammunition that were fed into the M1894 by a stripper clip.

A few years later, American gunsmith John Moses Browning developed the first successful semi-automatic shotgun, the Browning Auto-5, which was first manufactured in 1902 by Fabrique Nationale de Herstal and sold in America under the Browning name. The Auto-5 relied on long recoil operation; this design remained the dominant form in semi-automatic shotguns for approximately 50 years. Production of the Auto-5 was ended in 1999.

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