Once A Always A

I'm going out on a weak limb and speculating that the real reason that ATF is dropping charges in cases like Roh is how this upsets the apple cart with regards to other rulings they've pulled out of their asses.

26 USC § 5845 says:

The term “machinegun” means any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger. The term shall also include the frame or receiver of any such weapon, any part designed and intended solely and exclusively, or combination of parts designed and intended, for use in converting a weapon into a machinegun, and any combination of parts from which a machinegun can be assembled if such parts are in the possession or under the control of a person.

That seems pretty clear that a machine gun receiver is a machine gun, no?

Well...  There's only a tiny difference between a full-auto upper receiver on an AR and a "semi-auto"; a small relief cut for the auto-sear.  Wait!  Did I say difference?

There's hardly an AR made today that doesn't have that relief near the rear lug.

As near as I can tell, only Colt bothered to make an upper without them, and most of those also have the ginormous hole in the front lug for screws instead of a pin.

And people wonder why Colt lost the AR market?

But!  Should the AR's upper be ruled to be the serialized part, and that relief makes it "designed to shoot" automatically...  Also, since it's the work of seconds to plug in a lower with all the fun parts, they're also readily restored...  H&K had to redesign their upper on the Model 91 because full-auto trigger packs plopped right in.

There are a METRIC fuck-tonne of unregistered machineguns out there.  A large enough number that it's far more reasonable to do an amnesty than to attempt to get them all on the registry.

Another ruling that's out of their ass is the once a machinegun, always a machinegun.

For some guns, it's really difficult to undo the receiver so that it's can't be readily restored to automatic fire.  For most, though, it's not rocket science.

Take, for instance, the M14.  What really sets the receiver off from an M1A is the lug towards the rear of the body which houses the selector and where the automatic connector's rear rides.  Cut off this lug and it's no different from an M1A and is no more readily restored to than an M1A can be converted to.

Another thing pulled from their asses is what, exactly, constitutes "readily restored".