^Salient points, but I tried to keep it under 100 words. Could use some syntactic improvements, but what annoys and amuses me is that the source for my list at
https://www.law.cornell.edu/constitution/billofrightshas an "explanation" after each article.
Now you understand, I did not read the "explanations" but it always struck me that the originals were pretty plain English... especially the second one. Its brevity alone kinda makes it sound like they really really really meant it.
"What federal laws says the FFL has to put a serial number on the gun?"
Say what now?
As far as I know, there is no such law. Serial numbering is the responsibility of the manufacturer.
This issue might be confused with the requirement that (for a while?) importers of firearms had to put new unique "importer" serial numbers on the firearms they were marketing. Don't know if that's still the case.
However, there are many firearms (especially from Italy) without any, let alone importer's, serial numbers out there. My information is that when Italy wanted to export Carcanos, they re-barreled most of them, and
the serial numbers appeared on the barrel instead of the receivers. However, the Italian gunsmith who did the job did not have new barrels with serial numbers, so went ahead with the replacement. Therefore, there are many Carcanos out there without serial numbers at all. That was one of the later reasons, I understand, for coming up with the "importer's serial number" requirement.
I did have much of that data linked on an old computer, so that's my recollection, accurate or not, on the "new" serial number requirement.
I'm not sure how this fits in with the OP's reports, but AFAIK, you can build and keep your own firearm without a serial number until you transfer it. This, I presume, was because of the government's original desire to
not inhibit inventions and new developments in the firearms field.
A noble goal, unless you're of the delusional opinion that the whole world will live in peace and love and warm fuzzy contentment for ever and ever and ever and guns will not be needed or allowed. An idea that should have been universally rejected by any reasoning American on a September morning 22 years and 2 days ago.
Terry, 230RN
NOTE This inevitably brings up discussion of the Kennedy-Oswald Carcano rifle. See
https://en.wikipedia.org/wiki/John_F._Kennedy_assassination_rifleEDITED to add "guns will not be needed or allowed."