Correct, it must be marked anything but rifle or shotgun. Pretty strange that you cannot build a pistol from a rifle lower, yet you CAN switch a pistol to a long gun and switch back with no violation of the NFA.
You CANNOT have a barrel shorter than 16" in your possession without having a designated "pistol" lower OR an NFA stamp. If you do, it's a violation of the NFA.
See
U.S. v. Thompson/Center Arms Co., - U.S.- (1992)
As Mr. Bardwell explains:
This is another recent examination of the meaning of the language of the NFA by the Supreme Court, along with Staples. Neither involves constitutional law. In this case the court was called upon to decide what constituted a short barreled rifle. T/C wanted to market a kit consisting of one receiver for their Contender gun, a 16"+ barrel, a >16" barrel, a pistol grip and a shoulder stock. This kit could be used, as intended, to assemble a rifle or a pistol, or it could also be used to assemble a SBR. As it could be so used, ATF decided it was a SBR. T/C made one unit on a Form 1, then sued for a tax refund, claiming it wasn't subject to the NFA. This is the way to challenge such a classification. Doing the thing York or SWD did, in those cases, is an invitation to a prosecution. The Staples case will limit such things, but one can easily lose....Here all that was at stake was money. The court decided that the language of the definition of a SBR was vague, and gave it the reading most favorable to the taxpayer, T/C. They decided the kit was not a SBR, nor was any set of parts where they could be used for a legitimate purpose, even if they could also be used to assemble a SBR. However a SBR fully assembled was also clearly a SBR. Thus the other grey area was a SBR in parts form, like an Uzi carbine and a Uzi SMG barrel. A lower court had held in a prior case that that set of parts was a SBR. The (Supreme) Court agreed; that if the parts had only one use, to make a SBR, and a person possessed them all that was a SBR also.
Note the boldface sentence: Owning a rifle lower receiver (and no pistol lowers) while also owning an upper with a barrel under 16" is illegal according to the U.S. Supreme Court. Because you have all the parts necessary to assemble an SBR, but no way to use them legally without creating an NFA item, you are in possession of an unregistered SBR.
Ya think...........LOL.
