In this Feb. 1, 2013 photo, an employee of North Raleigh Guns demonstrates how a "bump" stock works at the Raleigh, N.C., shop. The accessory devices, which legally allow a semiautomati

 

              In this Feb. 1, 2013 photo, an employee of North Raleigh Guns demonstrates how a "bump" stock works at the Raleigh, N.C., shop. The accessory devices, which legally allow a semiautomati
In this Feb. 1, 2013 photo, an employee of North Raleigh Guns demonstrates how a "bump" stock works at the Raleigh, N.C., shop. The accessory devices, which legally allow a semiautomatic rifle to fire like a real machine gun, are among nearly 160 weapons or accessories targeted by a proposed federal ban. The federal government first restricted the possession of automatic weapons in 1934, in the wake of such gangland shootings as Chicago’s infamous St. Valentine’s Day Massacre. In 1986, the National Firearms Act was amended to prohibit the transfer or possession of machine guns by civilians, with an exception for those lawfully possessed before the law's effective date. (AP Photo/Allen Breed)