ATF Form 1 Question

For SBRs I thought it was once you register a certain length/caliber you can change to whatever you want as long as you still have the original setup as well...like if you went to sell it.

I need to do my sbr registration again...they denied at the last min because I left off the "jack" before the serial number.

Not exactly sure what you mean by 11" suppressor. Are you talking about the barrel length? I was told by several people that you can go longer, but not shorter.

Form 1 allows you to manufacture a suppressor.

Your probably thinking correctly

Form 4 is if you buy a suppressor/ already built SBR

Form 1 is if you build SBR (buy lower) or BUILD suppressor. Like machine your own.

This above post is mostly correct as were a couple of the previous posts. All caveated with fhe fact that you can get a different answer from just about anyone answering the phone at ATF on any given day.

The TECHNICALLY correct answer is this. If you want to change the length of a SBR from what is on the Form 1 you are supposed to write a letter to NFA Branch listing the firearm info (s/n, model, cal) and state that you are changing the characteristics (OAL and barrel length). They then file the letter with your original Form 1. If you are going to keep the original upper as well and swap them back and forth, state that as well. FWIW, I haven't heard of anyone ever being prosecuted for having a registered SBR that doesn't match the Form 1 specs. Not even sure what Statute would apply there.

I would guess, as far as a suppressor goes, this wouldn't work because the tube is the registered part and you can't substantially modify it after manufacture (read up on damaged tubes for more on this). I know Silencerco has some cans out now that can be made shorter/longer by adding sections so all of this may be in flux as far as silencers go.

FWIW, my source for the SBR info was from the Chief of NFA Branch who was a personal friend and I asked him. So I am going to say that is a pretty solid reference.