For a little over two years, this question has sparked debate that rivaled the “shoulder thing that goes up” debacle. At some point in 2017, AR-15 owners noticed that Sig Sauer introduced a “stabilizing brace” for AR-15 pistols. Originally intended to be strapped around the forearm for better recoil control, the brace started being used as a buttstock of sorts. Folks saw this unintended function as an opportunity to build a legal, pseudo-SBR with no paperwork: They would buy an 80 percent lower, build it, slap on a pistol upper, and throw a brace on their buffer tube. Boom, AR-15 pistol you can shoulder – or at least, could.
But it’s 2019 and the debate raged on until just recently. Can you still shoulder a pistol brace?
2017: ATF issues ruling on pistol braces
Angry politicians started crying foul of the Sig shoulder brace saga in 2017. The ATF released a statement in March 2017 to attempt to clarify the legality of this new, unofficial practice:
“With respect to stabilizing braces, ATF has concluded that attaching the brace to a handgun as a forearm brace does not ‘make’ a short-barreled rifle because… it is not intended to be and cannot comfortably be fired from the shoulder. Therefore, an NFA item has not necessarily been made when the device is not re-configured for use as a shoulder stock – even if the attached firearm happens to be fired from the shoulder.”
Basically, the ATF said no, shouldering a pistol brace does not make your AR-15 pistol a Short-Barreled Rifle (SBR) and thus, an NFA weapon. Some political leaders were quite unhappy at this clarification. After two more years of news cycles, legal talk and debate, the ATF released a final letter.
2019: The ATF issues a final ruling
Here’s what Max Kingery, acting chief of the ATF’s Firearms and Ammunition Technology Division, had to say on the matter one last time (you can read the full letter here):
“The pistol stabilizing brace was neither ‘designed’ nor approved to be used as a shoulder stock, and therefore use as a shoulder stock constitutes a “redesign” of the device because a possessor has changed the very function of the item.”
Kingery continued, making the ATF’s final position on the matter quite clear:
“Any person who intends to use a handgun stabilizing brace as a shoulder stock on a pistol (having a rifled barrel under 16 inches in length or a smooth-bore firearm with a barrel under 18 inches in length) must first file an ATF Form 1 and pay the applicable tax because the resulting firearm will be subject to all provisions of the NFA.”
So, there you have it: If you install a stabilizing brace on your AR-15 pistol with the intent of shouldering it, you’ve just built an SBR subject to the NFA Act. But what does that mean for your 80 percent lower build?
Can I still install a pistol brace on my 80 percent lower?
Whether you’re building an AR-15 pistol with an 80 percent lower or simply buying one, the answer remains the same: Yes, you can still install a pistol brace.
Installing one also does not automatically make your new AR pistol an SBR subject to NFA guidelines. The ATF’s ruling centers on intent (what you plan to do with it). Not the physical configuration of your pistol or the parts installed on it.
Can I still shoulder a pistol brace?
Officially, we must say no.
Intent is a funny thing when talking about legality. Intent is very difficult (sometimes impossible) to prove without physical evidence of that intent being carried out (or attempted).
But, let’s say you’re at the range with your AR pistol. You’ve got a brace installed and you throw that bad boy up onto your shoulder on the firing line. You may very well be showing “intent”. In fact, it might be quite difficult to prove you didn’t intend to shoulder your pistol when you installed your brace in the first place – or ever.
• In 2017, the ATF said that shouldering a pistol didn’t make your AR-15 pistol an SBR.
• In 2019, the ATF reversed course. They now say using a brace as a stock constitutes a “redesign”, making your pistol an SBR.
• They also say installing a brace with the intent of shouldering it makes your pistol an SBR (which is difficult to prove).
• You can still install a pistol brace on your pistol, you simply can’t shoulder it. Or ever intend to.
• Do yourself a favor, avoid showing any intent of shouldering your brace.