The device used to modify the firearm is known as a “bump stock.” Officials say it allows firearms to fire hundreds of rounds per minute. Unlike fully automatic weapons, which are strictly regulated under federal law, bump stocks are relatively accessible to civilians, with some advertised online for $100. “Converting a semiautomatic to fully automatic is very, very easy,” John Sullivan, lead engineer for the gun advocacy group Defense Distributed, told Wired. According to The New York Times: A bump stock allows the body of the rifle to slide a short distance back and forth, harnessing the recoil energy of each shot. “All of a sudden we heard what sounded like a machine gun and people just started screaming that they were hit and to get down,” witness Megan Kearny told NBC News.

Source: Huffington Post October 04, 2017 04:28 UTC