NFA Minimums
16 inch minimum rifle barrel length.
18 inch minimum shotgun barrel length.
(otherwise you have a SBR short barrel rifle
or SBS short barrel shotgun)
AND
26 inch minimum overall length.
On these minimums, it is smart to allow at least 0.5" OVER
(16.5, 18.5 and 26.5") to allow for repairs (recrowning a
damaged muzzle, broken stock, etc).
You can make an AOW "any other weapon" shotgun pistol
which basically is physically no different from a SBS "short
barrel shotgun" with a pistol grip. The AOW is built on a
"virgin" receiver never part of a regular shotgun. A SBS is
made by putting a short barrel (under 18*) on a regular
shotgun. Both require a Form 1 and $200.00 tax to make
but you cannot put a shoulder stock on an AOW because
that would make it a SBS, while a SBS can have either a
pistol grip or regular stock. That is for a maker; the AOW
transfer tax is only 5.00 and the SBS transfer tax is 200.00
so there is an advantage to AOW over SBS for commercial
purchase. For a Form 1 builder the SBS is more versatile.
NFA makes me dizzy.
BATF also has rules on converting an AOW or SBS to a
regular shotgun and removing it from the NFA registry;
why a person would do that after going through a Form 1
process and paying a 200.00 tax is hard to understand.
It can be done.