What Is a Bump Stock and How Was It Used in the Las Vegas Shooting?<br />“The classification of these devices depends on whether they mechanically alter the function of the firearm to fire fully automatic,” Jill Snyder, a special agent in charge at the Bureau of Alcohol, Tobacco, Firearms<br />and Explosives, said at a news conference in Las Vegas on Tuesday.<br />“Bump-fire stocks, while simulating automatic fire, do not actually alter the<br />firearm to fire automatically, making them legal under current federal law.”<br />Analysis of video posted on social media suggests that the gunman used rifles with rapid-fire capabilities.<br />The bump stock is not banned under federal law even though it allows a weapon to fire at nearly<br />the rate of a machine gun without technically converting it to a fully automatic firearm.<br />Twelve of the rifles the gunman in the Las Vegas mass shooting had in his 32nd-floor hotel room were<br />each modified with a “bump stock,” an attachment that enables a semiautomatic rifle to fire faster.<br />(It is illegal for private citizens to possess fully automatic firearms manufactured<br />after May 19, 1986; ownership of earlier models requires a federal license.)<br />The stock “bumps” back and forth between the shooter’s shoulder and trigger finger, causing the rifle to rapidly fire again and again.
