register a sbr on a homebuilt 80% lower?

[M1A Shooter]

im assuming this can be done as the manufacturer would be myself and i could mark it the same as if i were manufacturing any factory lower into an sbr but want to make sure.

i am looking to build an 80% lower. if i put my name and city on it as any other manufacturer and put a serial nmber on it, is this enough?

[Zak Smith]

As long as you have the required markings for both the firearm itself and the SBR I would expect it to be fine. I don't know of an ATF letter on this issue specifically, however.

Whenever doing something unusual, if you want to be as close to 100% covered as possible, write a technical inquiry letter to the ATF.