So here is the letter written by Marvin G. Richardson, Assistant Director of the Enforcement Programs and Services, to Mark Barnes, Esq and SB Tactical.

Mark Barnes Esq represented SB Tactical to help the ATF clarify their Open Letter from 2015. Everyone remembers that moment. It happened right before Shot Show 2015. The ATF published a letter detailing that shouldering a “Stabilizing Brace” constitutes a redesign since it was never designed to be shot from the shoulder.

This new letter starts off with a brief exposition acknowledging Mr. Barnes’ letter dated Jan 5, 2017. Then goes on to provide background on what the ATF determines as “firearm” and points out that the ATF approved the “arm-stabilizing brace” in 2012. This was the original SB Tactical brace which went on to become the “Sig Brace”

However constant poking of the bear, by the public, asking for clarification whether or not the Stabilizing Brace could be used as a shoulder stock is what led to the Open Letter in 2015.

Barnes’ letter asserts that misusing a brace is equivalent to using a wrench as a hammer or screw driver as a prybar and does not constitute “redesign”.

Now comes the important part which is the fifth paragraph.

The crucial part of the above paragraph is this line here.

What does that mean? While they do not specify the magic “length”, you should be wary of braces that are permanently attached to the end of a buffer tube that exceeds this specified “length”. The only braces that I can think of that fit this criteria are the GHW Tailhook and the Shockwave blade with the KAK pistol buffer tube. Take the Shockwave for example, when used with the KAK buffer tube there are 12 positions for the Shockwave blade to be affixed. That does position the Blade at a much longer length than any of the SB Tactical braces. That might be what the ATF is referring to. Same goes with the Tailhook being used on adjustable modified stock. Affixing the brace at the end of the buffer tube is not illegal. But if you do so and it results in making a super long brace then the ATF has a problem with that.

Marvin G. Richardson, Assistant Director of the Enforcement Programs and Services admits that the Open Letter was confusing and now have clarified their position.

Now this letter is directed to and for SB Tactical. I do not know if this applies to other braces like the Shockwave Blade or the GHW Tailhook. I would surmise it does not. Given the fact that repeated “poking of the bear” caused the Open Letter to happen I say leave well enough alone. You got a pistol with an SB Tactical or Sig Brace? Shoulder it to your hearts content. Just leave them alone and don’t mess with them.