One of the first things Congress is going to have to do when it starts debating an assault weapons ban is define "assault weapons." The National Rifle Association and a lot of gun owners say gun-control advocates and journalists misuse the term -- in fact, that they don't know anything about guns.

And it kind of stands to reason, if you don't own one -- or shoot one -- why would you know much about guns? It's not like people just hang out in gun stores if they don't shoot. Right?

On Tuesday, I drove to Chantilly, Va., 45 minutes west of Washington D.C., to Blue Ridge Arsenal. It's a gun store with an indoor target range, in an industrial park, two or three miles from Dulles International Airport.

"It's a pretty nice place, actually," says Mark Warner. He's the manager, and he seems to know everybody.

Warner has worked here full-time since 2004. He has a culinary degree, but his first job was as a security guard. Warner taught gun training classes.

While I wait for him, I look at the knives and handguns in glass display cases. Rifles and shotguns hang on the wall. There are maybe a dozen customers. Some of them are shopping. Others are waiting for a chance to shoot.

"While they're waiting, they love to chit-chat about, you know, current events and, you know, politics and all that stuff," says Warner. "And just general gun chatter."

We make our way past a leather couch to a table -- the kind you'd find at a sports bar. Warner tells me it's "law enforcement and military day." They get a discount: 10 percent off ammo and accessories. But there are all kinds of people here.

"We've had bachelorette parties, bachelor parties," Warner says. "I've got a grandmother who comes in with her grandson, who is 6'5". And they come here, with a smile on their face. And they leave with a bigger smile on their face, because they enjoy the camaraderie of shooting. Hitting that bull's eye."

A middle-aged man comes in, to pick up a rifle. One of the four clerks does a background check. He calls Richmond, the state capital; gets an authorization number; the buyer signs some paperwork; and in 15, maybe 20 minutes, he's out the door.

Warner tells me he follows the letter of the law, and he won't sell a gun to just anybody.

"It's my choice to sell a gun to a certain person if I choose to," Warner says. "And I've had several people who have given me the eerie feeling to a point where we've actually called local stores and said, 'Hey, this person gave me this feeling,' or whatever. 'We didn't sell them a gun. Keep a heads up for them.'"

Warner waves over a guy in sweat pants who has been admiring the rifles. Paul Kunz says he is looking for a 1911 .45 ACP and a semi-automatic .30-06. Warner doesn't have either of them.

Kunz is 63 years old, and he says he shot a gun for the first time more than 50 years ago, at summer camp. It was a .22.

"That was my first introduction," Kunz says. "Classes on safety. Not to fear them, but to recognize them and respect them."

Kunz has been going to Blue Ridge Arsenal since it opened, in 1989, and he is what you might call a Second Amendment absolutist. He shows me his NRA membership card.

"I mean, if you attack one bullet, if you attack one gun, you're attacking everything," Kunz says.

Inside the range, everyone is required to wear safety glasses and ear protection. There's a woman, learning how to shoot, and a man, firing a semi-automatic pistol. Another guy unpacks an AR-15. Five minutes later, he lies on the ground.

It is louder than I expected. Bullet casings fly back at me.

Variants of this gun were illegal for a decade, when the Assault Weapons Ban was in place. Back in the shop, Mark Warner tells me that today, he can't keep them in stock. Fifty people are on the waiting list.

Warner just got back from a big gun show in Las Vegas. The mood there, he says, was "sad." There weren't the usual deep discounts for dealers, and manufacturers said they wouldn't have firearms like that AR-15 for months, maybe a year.