Sig Brace illegal to shoulder

[MrDraco]

I wasn't sure where to post this, but if you're interested in building a pistol with thoughts of shouldering it with a Sig Brace on it, this is a good read.

http://www.m4carbine.net/showthread.php?...By-The-ATF

Looks like the ATF covered all their bases with that one.

Here is the question I am curious about. Can you shoulder an AR pistol with just the recoil tube on it and not commit a crime? You have not redesigned anything. : shrug :

That would not be enjoyable with 458 SOCOM or Beowulf but with 5.56 it is hard to imagine why you would need a stock anyway.

But page 4 has this letter.