IIRC, a Class 7 FFL (manufacturers Federal Firearms License) and a Class 2
SOT (NFA weapons manufacturing Special Occupational Taxpayer status). The
class 7 ffl is for any firearms manufacturing, like Remington, Ruger, Colt,
etc. The SOT is for National Firearms Act controlled items: machineguns,
silencers (sound suppressors), short barreled rifles (shorter than 16") and
shotguns (shorter than 18"), destructive devices (explosive devices, cannon,
and any firearm with a bore larger than .500" with exception made for
sporting shotguns and some safari size rifles), and Any Other Weapons (pen
guns, briefcase James Bond guns, also some makes of shotguns that were
originally manufactured with pistol grips and barrels later shortened).

Some forms, a background check, fingerprints, photos and a substantial
recurring fee. Not too substantial if you are going to make a living at it,
but big enough to discourage the casual interest. I am told when you figure
in all the fees it comes to about $1500/year.

Most forms require local chief law enforcement signoff.

There's more but I am too tired to remember it all tonight, maybe someone
else will chime in.

hth,

StaticsJason

"Tom Gardner" wrote in message
.com...
I have an idea for a new kind of full-auto weapon that I have been seeing
in
my head for a long time. I'm no where near ready to start machining stuff
yet but I am wondering how to do legal research and developing of the
idea.
So, do I call the ATF and say: "Hey I want to build a machine gun."? At
what point does it become a problem? It looks like I'll only need a few
pounds of unobtainium and some disapearium. The idea eliminates one whole
operation and could increase cycle rate by as much as 30% while
diminishing
recoil. It might do better if I could suspend some of the laws of
physics.