See why the device that made the Las Vegas shooting most deadly may be banned

HEMPSTEAD, Long Island — The device that enabled the Las Vegas shooter to kill as many people as he did could be banned if a congressional resolution being introduced next week gets passed.

A co-sponsor of the legislation, Rep. Peter King, a Long Island Republican, is making statements about the political move. The Nassau County Police Department is not.

Nonetheless, the department allowed PIX11 News to observe its training. Also, its firearm instructors provided clear explanations of the potentially deadly effect that the device, called a bump stock, can have.

The Las Vegas massacre, and the actions of police during and after it, are reminders of why police training is so important.

"We train constantly," Lt. Hodge Begis, director of the Nassau County Police Department firing range, said.

He was overseeing a live fire training of the department's emergency services unit, or ESU, on Friday afternoon.

Begis pointed out that his department's training closely simulates real-life scenarios. As a policy, the NCPD trains officers to use their firearms as a last resort only. Those service weapons are all semi-automatic, not automatic.

That means, Begis explained, "every time you pull that trigger, one round is fired."

A round is the tactical term for bullet. A semi-automatic live fire contrasts sharply with what Stephen Paddock did from his Mandalay Bay hotel room.

Few can forget the rapid-fire volleys that he rained down on concertgoers at the Route 91 Harvest Festival country music concert on Oct. 1. Paddock's fusillade killed 58 people and injured hundreds.

He used semi-automatic rifles to carry out the slaughter, but supplemented their lethality by attaching a bump stock to them.

Begis explained how the bump stock works.

"When the trigger is fired in semiautomtic mode," the head instructor said, "one round is fired, and the spring [in the device] makes [the rifle] go back and forward and it goes off immediately again.

"With some practice," Begis continued, "it'll sound like an automatic, and you can present it like an automatic weapon."

One of his fellow instructors used an UMP-45 rifle to demonstrate what an automatic weapon can do. The rifle can switch among three different settings: semi-automatic; semi-automatic blast, which releases a spray of a few bullets at a time; and automatic.

The UMP-45 on its automatic setting shot an entire clip of 32 rounds in three seconds, in a demonstration of firepower that the NCPD gave to PIX11 News.

That's a rate similar to how fast Paddock was able to shoot with his rifles at Mandalay Bay, thanks to the bump stock device.

"If it's a big target, like a crowd," said Begis, "it's going to be impossible to miss, unfortunately."

It's why King is co-sponsoring the resolution banning the device.

"There's no purpose for a bump stock, except to turn a legal weapon into an illegal weapon," King told PIX11 News.

The resolution is bipartisan, and, unlike every legislative bill in more than two decades that seeks to limit gun use, it actually may have the votes to pass.

There's no guarantee that it will. However, King said, "This is the first time in the 25 years I've been in Congress that there's a definite consensus that something has to be done."