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AUSTIN, Texas - When authorities searched Las Vegas shooter Stephen Paddock's hotel room they found some firearms that appeared to be modified rifles.
The Clark County Sheriff said the ATF is evaluating the weapons to determine exactly what was changed.
One alteration the sheriff mentioned is a bump stock, which can simulate a rapid-fire weapon.
The sales manager at Guns Warehouse in Cedar Park, whom did not sell any weapons to Paddock, explained what a bump stock does.
He said his store does not sell them, but they are available on the internet without a background check and they are 100 percent legal in Texas as well as Nevada.
For nine minutes Sunday night, rapid fire echoed from the 32nd floor of the Mandalay Bay Resort and Casino.
Experts said it sounded as if the shooter fired hundreds of times in mere seconds, something that would be extremely difficult to do with a semi-automatic weapon, unless the rifle used was modified.
“Legally there is no way to turn this semi-automatic rifle into a full automatic rifle. There are some parts that are legal for sale, the ATF has determined does not make it a machine gun, but does increase the rate of fire,” said Steve Ou, sales manager at Guns Warehouse.
A slide fire bump stock can take the place of a standard stock, using the gun’s recoil to help fire rounds more rapidly.
“I would think if you were placing this on your weapon, coupled with the fact that you were pulling forward, that it would affect accuracy. It would be much less accurate then if you were placing anything in single fire,” Ou said.
Because the bump stock still requires the trigger to be pulled for each shot, the ATF considers it legal. However, some states have their own laws banning the stocks.
For those looking for a rapid fire weapon, a bump stock is much easier to obtain than a fully-automatic firearm.
“If this was a registered receiver M16 you're probably looking at $15,000 on up, whereas this is about $160 and you don't have to go through a background check and there's no waiting period for this,” said Ou.
Because there is not a federal background check required, it is up to sellers whether to keep a record of bump stock sales. Over the last 48 hours, hundreds of the stocks have been purchased online, but gun sellers said, to them, that doesn't raise any red flags.
“This is the first, I think, mass shooting that I'm aware of that anyone's used this and this part has probably been on the market for close to five years,” Ou said.
If the ATF wanted to make bump fire stocks illegal they could change their definition of a machine gun.
Congress could also take action, something they chose not to do in 2013 when a bill was proposed banning the stocks.