Bump stocks were a novelty popular with YouTube gun enthusiasts wanting to simulate machine gun fire. Then they were found in a mass shooter’s arsenal

Gun control advocates are calling for a ban on “bump stocks”, the largely unregulated novelty devices which Las Vegas shooter Stephen Paddock may have used to convert a semi-automatic rifle into a weapon that mimics the continuous fire of a fully automatic weapon.

At least two bump stocks were recovered in Paddock’s hotel room, the Associated Press reported on Monday night, citing law enforcement sources. It is not yet clear whether they were used in his attack.

Las Vegas gunman may have used special device to fire faster, expert says Read more

Bump stocks attach to semi-automatic weapons and harness the recoil of the gun to allow a shooter to fire much faster than they could do if they repeatedly pulled the trigger – as the rifle recoils, the trigger bumps forward into the shooter’s finger to speed up the rate of fire.

As one company that sells the devices, Bump Fire Systems, put it on its website: “Did you know that you can do simulated full-auto firing and it is absolutely legal?” It listed the price of one stock at $99.99.

Gun experts called bump stocks a “toy” and “something a gun geek would want”, not a mainstream product or a tool for serious shooters who care about accuracy. Before Sunday’s attack, bump stocks featured prominently in gun enthusiast stunt videos on YouTube.

Democratic senator Dianne Feinstein, who authored the 1994 ban on assault weapons and has tried unsuccessfully to renew the ban in recent years, said in a statement on Tuesday that she has advocated banning bump stocks for years.

“This is the least we should do in the wake of the deadliest mass shooting in US history. It should be our highest priority,” Feinstein said.

“Hardware that turns legal guns into automatic weapons should be prohibited,” Shannon Watts, the founder of Moms Demand Action, one of America’s largest gun control groups, wrote on Twitter. “Automatic weapons are highly regulated; this evades federal law.”

David Chipman, who spent 25 years as an ATF agent and now works as a policy adviser for Americans for Responsible Solutions, a gun control group, said the bureau has repeatedly confirmed that bump stocks and similar devices are not strictly regulated under the National Firearms Act or the Gun Control Act.

Bump stocks allow rapid fire “by throwing the trigger against your finger as opposed to your finger pulling on the trigger”, he said. He called the device “a masterful creation of a technical workaround creating a loophole to circumvent the intention of the law”.

Facebook Twitter Pinterest A ‘bump’ stock lies next to a disassembled .22-caliber rifle at North Raleigh Guns in Raleigh, North Carolina. Photograph: Allen Breed/AP

Rich, a refinery operator from Wilmington, Delaware, who owns more than 40 guns, said he bought a Bump Fire Systems device for about $100 two years ago because it was “the closest thing that I could have that would simulate a machine gun”. Delaware, where he lives, bans the ownership of machine guns, which he would otherwise add to his collection. He requested that his last name not be published so he could candidly discuss his large gun collection without fearing that it might be targeted by thieves.

Purchasing the bump stock did not required a background check, he said. “It’s just like ammo: you order them online, they ship them to your house.”

The device was fun as a “range toy”, but tricky to master, and very difficult to fire accurately. “This thing requires practice,” he said. “It’s not something that somebody off the street could do the first time.”

Many gun stores do not sell bump stocks, perhaps because they might attract “the wrong kind of crowd”, he said, meaning “irresponsible gun owners, people that they watch YouTube videos [and go], ‘Hey, I guess I don’t own a machine gun now,’ and they go out and they do things without seriously thinking about the impact of what they’re doing.”

Many shooting ranges do not allow bump fire devices for a similar reason, he said.

“I got my fun out of it but the novelty kind of wore off,” Rich said. “It’s definitely not reliable as a self-defense method or anything else.”

He said on Monday night that he expected the devices would face intense scrutiny, and that some politicians would call to ban them, which he said would be regrettable.

“I don’t want to see anything banned because of the actions of one person,” he said. “That just doesn’t jive with my principles of freedom.”