What defines a "gun"?

[sperman]

If I want to buy a gun from a local dealer, I have to fill out all kinds of paperwork, and show a CC permit or a purchase license (NC.) But I can go to midway and buy a reciever, slide, barrel, trigger, etc. and build one from scratch. Any idea how the government would view this weapon?

[chp5]

Generally the reciever is the "firearm." You can buy everything but the receiver without going through an FFL.

[Jman]

Midway won't send Joe Lunchbox a frame or a receiver. But will send it to your FFL for the normal transfer. That is if I have all the facts.

Jim M

[J-Ho]

Each type of firearm has a part that is the 'gun' the frame for most pistols, the lower receiver for an AR, the upper receiver for an FAL. If you are not sure call your local ATF. My local office is really a pretty good group of guys. interestingly, muzzleloading weapons are not firearms according to ATF. This includes black powder revolvers and even cannons.

[Vlad]

This guys covered it pretty well except for the tax issue. If I'm not mistaken if you build your own from parts you are also not paying the added tax for a complete firearm. However if you ever sell it you owe someone that tax.

[Rob Boudrie]

Generally the reciever is the "firearm."

This is the case with federal law. State laws vary.

Here in the Massachusetts, a stripped lower is not legally a gun. If I go to a shop to buy a gun, I fill out state forms + the 4473. If I buy only a stripped lower, I only need to fill out the 4473 and don't even need a state gun license (although some shops treat the stripped lower as the gun, they are not required to under MA law). This really helps people getting custom guns built due to the rather bizarre laws and regulations limiting the dealer sale of new handguns to only specific models (for example, you can buy an SVI new but not an STI; you can buy a Para 1911 but not a Kimber or Springfield; etc; etc.).

[vluc]

IIRC (and I may not), in Europe, the slide is the gun, not the frame. Opposite of here.

[Dan Sierpina]

IIRC (and I may not), in Europe, the slide is the gun, not the frame. Opposite of here.

Also, some countries serial number the barrel.