In the United States, the assault rifle design was later in coming; the replacement for the M1 Garand of WWII was another John Garand design chambered for the new 7.62×51mm NATO cartridge; the select-fire M14, which was used by the U.S. military until the 1960s. The significant recoil of the M14 when fired in full-automatic mode was seen as a problem as it reduced accuracy, and in the 1960s it was replaced by Eugene Stoner's AR-15, which also marked a switch from the powerful .30 caliber cartridges used by the U.S. military up until early in the Vietnam War to the much less powerful but far lighter and light recoiling .223 caliber (5.56mm) intermediate cartridge. The military later designated the AR-15 as the "M16". The civilian version of the M16 continues to be known as the AR-15 and looks exactly like the military version, although to conform to B.A.T.F.E. regulations in the U.S., it lacks the mechanism that permits fully automatic fire.