Full-automatic

An automatic rifle is a type of magazine-fed rifle that uses either its recoil or a portion of the gas propelling the projectile to remove the spent cartridge case, cock the rifle, load a new cartridge and fire again repeatedly, as long as the trigger is held down or until the magazine is exhausted. Automatic rifles are distinguished from semi-automatic rifles in their ability to fire more than one shot in succession once the trigger is pulled. Many automatic rifles are select-fire weapons which are capable of firing in fully automatic and semi-automatic modes, or in some cases, even being capable of burst-fire. Most are further subcategorized as battle rifles or assault rifles.

The world's first automatic rifle was the Italian Cei-Rigotti. Introduced in 1900, these 6.5mm Carcano or 7.65×53mm gas-operated, selective-fire, carbines attracted considerable attention at the time. They used 10-, 20- and 50-round detachable box magazines. Unfortunately, they had several failings, including frequent jams and erratic shooting. In the end, no Army took an interest in the design and the rifle was abandoned before it could be further developed.

The Browning Automatic Rifle (BAR) was one of the first practical automatic rifles. The BAR made its successful combat debut in World War I and approximately 50,000 were made before the war came to an end. The BAR arose from the concept of "Walking Fire", an idea urged upon the Americans by the French who used the Chauchat light machine gun to fulfill that role. The BAR never entirely lived up to the designers hopes; being neither a rifle nor a machinegun. "For its day, though, it was a brilliant design produced in record time by John Browning, and it was bought and used by many countries around the world. It was the standard squad light automatic of the U.S. infantry during World War II and saw use in every theater of war." "The US forces abandoned the BAR in the middle 1950s, though it was retained in reserve stocks for several years; it survived in smaller countries until the late 1970s."

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