Measuring SBR overall length for Form 1

[kidicarus13]

Measured from end of buffer tube, end of collapsed stock, or end of extended stock. I've found all three methods on the interwebs.

[275RLTW]

Go with the shortest possible. You can always go longer without having to file for another stamp, but not shorter. There's a thread on this already with good info in it.

[brutal]

Assuming adjustable stock, I've always filed length of extended stock as that's what I've read from the regs. Reg is barrel less than 16" OR less than 26 OAL.

Besides SBR=SBR=SBR once approved and stamped. Doesn't matter what you put on it, or what length you make it after it's an SBR unless you permanently alter the configuration.

FWIW, I filed a form1 on a 27.5 OAL (extended) 9" 300BLK and it was approved.

[Ramsker]

I asked that question on the ATF "ask the experts" page because I had heard it different ways . . . they replied "extended".

[kidicarus13]

Another member directed me to https://www.atf.gov/file/11281/download

Page 8, under (2)(j)(5)

Appears to answer my question.