BREWINZ
NES Member
Completely new to the form 1 and NFA world. If you would allow me to state what I think I understand and ask some questions it would be greatly appreciated. Please feel free to correct me where I'm wrong.
Project: I am using a POST-1994 AR lower to build a 9mm SBR.
1. I am building a 9mm SBR from an Anderson AM-15 multi cal lower. On form 1, section 4c, I should input the caliber as 5.56mm because I am using a Stern Defense Glock 9mm mag adapter which can be removed. Thus, the true caliber of the receiver is 5.56/.223.
2. Upon tax stamp acquisition, I can install an SBR 9mm upper. I can also remove the mag adapter and use separate upper for a different caliber. 5.56, .300 Blackout, etc.
What I'm really unsure about is section 4e and 4f. Should I put the lowest length the barrel and overall rifle could possibly be or is an SBR receiver covered for all lengths under 16" and 26", respectively, once the tax stamp is obtained? I don't know if an SBR is an SBR or if the ATF cares about a few inches.
Project: I am using a POST-1994 AR lower to build a 9mm SBR.
1. I am building a 9mm SBR from an Anderson AM-15 multi cal lower. On form 1, section 4c, I should input the caliber as 5.56mm because I am using a Stern Defense Glock 9mm mag adapter which can be removed. Thus, the true caliber of the receiver is 5.56/.223.
2. Upon tax stamp acquisition, I can install an SBR 9mm upper. I can also remove the mag adapter and use separate upper for a different caliber. 5.56, .300 Blackout, etc.
What I'm really unsure about is section 4e and 4f. Should I put the lowest length the barrel and overall rifle could possibly be or is an SBR receiver covered for all lengths under 16" and 26", respectively, once the tax stamp is obtained? I don't know if an SBR is an SBR or if the ATF cares about a few inches.
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