I would like to add that some types of private security companies fall in that police force category. Your situation is a question for the batfe itself. The nfa folks arent the ogres some make them out to be. They arent "out to get you" and are actually very helpful. I would suggest, in your case, contacting the nfa branch of the batfe directly.
"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." — L. Neil Smith
The problem with being stupid is you cannot simply decide to stop doing dumb things...
"I crapped my pants to avoid the draft!!" -Ted Nugent