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.