I called the FRB from work today, safe to do because we have 400 employees and a phone bank, every time you make an out going call it gets a different number, so it is very hard to trace. I asked the anonymous question about trading a gun to Kittery 10 years ago and how to handle, just to get their take on it, and they confirmed that there is nothing you can do about an FA10, and that if they did do a search and seizure the gun would be in the Federal database even if I didn't have the records and "hopefully" they would take my word and check with Kittery or the Feds before knocking down walls.
Of course I try to stay squeeky clean and the shotgun I traded hopefully is never used in a crime.
of course I worry about that about as much as I worry about an asteroid or the Federal sequester affecting me. I was just being curious.