GLENDALE, Calif. (FOX 11) - It was the sound of rapid fire gunshots that sent Las Vegas concertgoers running for their lives. Stephen Paddock's ability to kill and injure so many people may have come from a device used to increase the firing speed of a semi-automatic weapon.
Inside his Mandalay Bay hotel room officials said they found 23 weapons along with two devices called 'bump fire' stocks.
"It's a stock replacement that allows the recoil of the firearm to reset the trigger rather than you having to take your finger off the trigger and firing it again," Pete Brown, with American Gun Works in Glendale, explained.
Brown said the stocks are generally used for sport. "This is a toy," he said. "It''s something that you get if you just want to blow away the hillside."
YouTube videos from bump stock manufacturers show the firing power of guns equipped with the stocks.
"It depends on the cyclical rate of the firearm itself that can be as low as say 200-rounds per minute or it can be 600-rounds a minute," Brown said.
It takes skill to master the device, which doesn't provide the shooter much accuracy, according to Brown.
He's decided not to carry them in the store for a variety of reasons. "We decided there's really no use for this thing I mean legally it falls into a grey area," he said.
Depending on how California law is interpreted, the stocks could be considered a trigger activator.
Some lawmakers have come out against the device. "Which can be added to an AR-15, which essentially makes it mimic automatic weapons and it's legal," Sen. Dianne Feinstein, D-California, said.
She introduced a bill several years ago that would have banned the device.
"There's no conversion, a semiautomatic weapon is a semiautomatic weapon with a bump stock it's still a semi automatic weapon," Brown said.
It's not known whether or not Paddock actually had the stocks attached to his rifles used in the shooting.
"He didn't find targets, he didn't aim at targets, he just filled this area with as many bullets as he could put out there," Brown said.