This is something I've just thought about. If I purchase a stripped lower, purchase it as a pistol. I could have it with any barrel length I wanted, but with no but stock. So essentially I can build a SBR, but not have it be a SBR? As long as it does not have a buttstock, or forward pistol grip, I should be safe. But then I thought about what IF i wanted to put it on a form1 as an SBR. Could I still keep it as a functional pistol until I received the Tax stamp? I'm sure the local SOT could anwser this better, but I was wondering if anyone knew how this works?