Foxhole in gainesville told me that a "other" receiver could not legally be built into a pistol and referred me to their attorney who specializes in firearms.. but I realize many attorneys are arrogant and make plenty of dumb mistakes as anyone else so I scoffed it off.
I believe you're wrong about the "rifle first" rule always standing, example:
Sam buys a colt 6920 lower from a individual on gunbroker and Sam has it shipped to his local FFL dealer ABC guns. Later, Sam swings by ABC guns, fills out the 4473 and ABC checks "other" on the form. Sam goes home and builds a pistol with the colt lower while legally standing behind the last 4473 filled out on that colt other lower, Right?
The thing that bothers me here, is that the ATF doesnt have any new documents on their website pointing to what this lawyer is saying. If I'm not looking in the right place can someone please point me in the right direction?
Also, is it worth the hassle or should I just sell my lower and buy a marked pistol lower from Aero precision and call it a day?