Re: sbr questions
All NFA stuff is similar in terms of the BATF process.
Form 1 to make, Form 4 to transfer, or Form 3 for SOT to SOT transfer.
Form 1 & Form 4 are normally $200 unless it is a tax exempt transfer.
The way it was explained to me, for a Form 1 SBR was that you can put whatever barrel length you want on it, but you must be able to restore it to the configuration listed on the Form 1.
(ex. My Form 1 SBR is for a 10" barrel, but I also run a second upper with a 14.5" barrel.)
If the changes cannot be undone, you must contact the BATF and have the Form 1 amended to reflect the permanent change.
For a Form 4 SBR, it is my understanding that the same rules apply, but I'm not sure whether or not you can ammend the form or not.
Please do not treat this as the gospel though.
I do not have a letter from the BATF stating this nor do I have any references to support it.
If anyone has more accurate information, please correct me.