Bump stocks selling out in U.S. after gunman used them in Las Vegas shooting

Some American gun stores are reporting that bump stocks, which allow semi-automatic weapons to fire as quickly as machine guns, are selling out. They were used by the shooter in the Las Vegas massacre.

Police said Stephen Paddock outfitted 12 of his firearms with bump stocks before firing into a crowd of 22,000 people at a country music festival, killing 58 people and injuring hundreds of others in Las Vegas on Sunday night.

Since the shooting, some online gun manufacturers say they have sold out of the devices.

READ MORE: Gunman used ‘bump-stock’ device to speed fire in Las Vegas shooting

Slide Fire, a Texas-based manufacturer of bump stocks, appeared to have sold out of them, as the company posted to customers on its website: “We have decided to temporarily suspend taking new orders in order to provide the best service with those already placed.”

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Another Texas-based bump stock manufacturer, Bump Fire Systems, posted on its website, due to “extremely high demands” the company stopped taking order to better ensure customer service.

On the company’s Facebook page, it read, “Currently our servers are down due to high traffic volume. Please be patient, our IT Dept is currently working on the issue as fast as possible.”

Firearms retailer militarygunsupply.com, also appeared to have run out of bump stocks.

Gun sales typically rise after mass shootings, as many buyers believe the government will pass legislation to regulate or ban guns. After the Las Vegas shooting, share prices in gun companies rose sharply, as investors bet fear will lead to a surge in gun sales.

Bump stocks are legal

Fully automatic weapons, like machine guns, are banned in the U.S., but semi-automatic weapons, which fire a single bullet each time the trigger is engaged, are legal and widely available. So are bump stocks, which manipulate the trigger mechanism extremely rapidly, far faster than a person could do so without them.

The device basically replaces the gun’s shoulder rest, with a “support step” that covers the trigger opening. By holding the pistol grip with one hand and pushing forward on the barrel with the other, the shooter’s finger comes in contact with the trigger. The recoil causes the gun to buck back and forth, “bumping” the trigger.

Despite it being legal, bump stocks have attracted scrutiny from authorities and lawmakers in recent years.

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Lawmakers may clamp down

Since the Las Vegas shooting, a debate started circulating in Washington over regulating firearm ownership. On Thursday, the White House said it was open to taking part in a “fact-based” discussion on the devices.

“We know that members of both parties and multiple organizations are planning to take a look at bump stocks and related devices,” White House spokeswoman Sarah Sanders told reporters.

“We certainly welcome that and would like to be part of that conversation,” Sanders said.

WATCH: White House says it’s ‘open’ to talks on banning ‘bump stocks’ for guns

0:28 White House says it’s ‘open’ to talks on banning ‘bump stocks’ for guns

Republicans, who currently control the White House and both chambers of Congress, have fought off Democratic calls for stricter background checks or federal limits on magazine size following past mass shootings.

But even congressional Republicans have said they would be willing to investigate bump stocks.

Earlier Thursday, Republican U.S. House Speaker Paul Ryan said lawmakers need to examine bump stock accessories. He added that many lawmakers in the Republican-controlled Congress had not been aware until now that such devices existed.

“Clearly that’s something we need to look into,” Ryan told MSNBC.

Tweet This Click to share quote on Twitter: "Clearly that's something we need to look into," Ryan told MSNBC.

In a surprise announcement the National Rifle Association — a powerful opponent of gun control initiatives — said on Thursday it would support efforts to regulate the devices.

— With files from Reuters