Is it against the Law to own a Grenade Launcher

[gagtoe]

I just picked up a 37mm from here this morning. I can shoot anything that's not "anti-personnel" smokes, flares, etc. I will end up DD'ing mine on a Form 1 so I can use actual 12 gauge rounds in it. They sell two types of 12 gauge adapters, one that will only allow the short flare rounds, and one that is fully 12 gauge capable.