You dissed him for saying that California and maybe Oregon might require serial numbers. Well in fact California and Connecticut require even 80% unfinished to have them. So state law trumps ATF.
His words, "You must also mark it per
federal guidelines." I'm only contesting federal part. I have no issue with the advise on someone educating themselves on state/local laws concerning the legality of a non-licensed individual making firearms. A few people have run afoul with LE due to the process they used to finish 80% lowers...
