Gear, Parts and Accessories

SIG’s SB15 Legal Pistol Stabilizing Device

Picture shows a black pistol stabilizing brace.

In November 2012, disabled veteran Alex Bosco received a letter from the ATF regarding a prototype of a stabilizing brace he invented to aid him in shooting an AR-15 pistol one-handed. The device, called SB15 made of medical-grade rubber—the same type of material used to make prosthetics—fits over the buffer tube of AR-15 pistols. After slipping the device over the AR-15 pistol’s buffer tube, the user is then supposed to secure the pistol-stabilizing device around their forearm using the two attached Velcro strips.

Picture shows SIG Sauer's ad for the pistol-stabilizing device
SIG Sauer’s marketing reminds us the product is supposed to be strapped around the user’s forearm to aid in shooting the AR-15 pistol better.

SIG Sauer since purchased the pistol stabilizing brace design from Bosco and now sells it separately and on its PM400 AR-15 pistols. Century Arms also found a way to put the brace on an AK-47 pistol and sell one that fits the PAP M92 PV, PAP M85 PV, Draco, and C39 pistols called the SB47.

Many people began using the brace to shoulder their weapons, instead of shooting them one-handed. The device looks similar to a TAPCO AR-15 rifle stock. When using the stabilizing brace to shoulder the weapon, the AR-15 and AK-47 pistols look deceptively like a short-barreled rifle (SBR). Though legal, the ATF considers the short-barreled rifle a Title 2, Class 3 restricted weapon requiring a tax stamp, paper work and registration with the ATF. To learn more about building and owning an SBR, read “How to Build a Short-Barreled Rifle (SBR). Of course, “misuse” of the product drew questions from the gun community.

The ATF went on record saying the SB15 and SB47 pistol-stabilizing device classifies as a “forearm brace” and since intentionally designed to aid in shooting the AR-15 pistol one-handed, putting the device on your pistol and shouldering it does not constitute turning your pistol into an SBR.

Since the ATF classifies firearms strictly based on its “physical design characteristics” using the device against your shoulder does not make the pistol illegal.

The ATF and Bosco want you to know, however, that shouldering the pistol with the use of the SB15 or SB47 is not the manufacturer’s intended purpose and therefore constitutes “improper” use of the product. You will not see SIG Sauer displaying improper use. In fact, SIG Sauer’s marketing reminds us the product is supposed to be strapped around the user’s forearm to aid in shooting the AR-15 pistol better. The company also donates a portion of the proceeds of each sale made from the SB15 to the Honored American Veterans Afield Organization. Remember, Bosco developed the brace to allow shooters with the use of only one hand to shoot the AR-15 and other similar pistols. Those without much strength in their arms due to age or injury will also find the brace beneficial.

Though the brace fits over pistols with 1 to 1.2-inch AR-15-style buffer tubes, the gun community is an ingenious lot by finding other ways to “improperly” use the SB15. Modeling after Century’s AK-47 pistol with the brace, I know others who have fashioned their own connectors to attach the SB47 on their AK-47 pistols using few parts. The owner of the setup I met calls his set up “essentially an SBR without the paperwork.” Using a machinegun hinge, “pig nose adaptor” and an AR-15 buffer tube, he made a folding SB47 for his AK pistol.

Demonstrating the brace properly, by attaching it to his forearm, the owner showed me how he could not see the sights properly and had to turn the gun gangster style—by tilting the gun sideways—to get any kind of sight picture. However, when putting the brace up against his shoulder, the sight alignment worked out as is should.

He told me the brace makes the otherwise hard hitting AK-47 pistol a rather soft shooter, due to how soft the rubber on the brace is, making it an excellent recoil absorber.

AR-15, AK-47 and other pistol-grip only type carbines are difficult to shoot. I have met plenty of people who do not see the point in one, but with this brace making them easier to aim, shoot and control. These types of pistols make great home defense weapons and truck guns. In fact, his AK-47 pistol with the SB47 attached folds up to fit in his gym bag—and all perfectly legal.

Picture shows a black pistol stabilizing brace.
Century Arms also found a way to put the brace on an AK-47 called the SB47.

At less than $150, I would say the SB15 and SB47 pistol-stabilizing brace is not just a fad, toy or gimmick. For those with disabilities, missing an extremity or injured, it allows you to enjoy shooting AR-15-and AK-47-type pistols accurately and effectively. In addition, for those without the budget for a tax stamp, or more importantly patience, the stabilizing brace provides the answer to the “poor man’s legal SBR”—of which there never was before.

Bosco’s product is truly innovative in concept and follow-through. As long as the ATF sticks to their word, I anticipate seeing the SB15 and SB47 a lot more. I don’t know one shooter who would complain about having one in their arsenal.

Buy the SB15 and SB47 online


What do you think about this product? Tell us your thoughts in the comment section.


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Comments (16)

  1. Statements calling for an “overthrow” of the government in this forum are misplaced and irresponsible. They do nothing but paint firearms owners as “gun nuts” and serve as ammunition for those who would see our rights severely limited or eliminated. Certainly the 2nd Amendment was put in place specifically to guard against a tyrannical government. However, as intrusive and even abusive as our government has or can be is nothing even approaching what true tyranny looks like. Disagree? Fine. But before you load up and head for Washington take a look at some of the real tyrannies in history. Germany WWII, Haiti before its most recent revolution, North Korea under the Un family, Belarus today… I could go on for quite a while but the point is simple. The citizens of the United States have never lived under real tyranny in this country.
    (And yes, the key word in that sentence is citizens. Our abuses during the expansion of the nation against the indigenous peoples and the treatment of those brought here as slaves are not a part of this discussion so I don’t need a mile of spam stating the obvious.)
    Despite the overly litigious nature of our society and it’s penchant for the nanny state, we still have more freedom than 99.99% of places on Earth. Enjoy the peace of this great nation and the luxuries that allows. Do not hasten days of lawlessness and chaos by wishing them here any sooner than may be inevitable.

    1. One caveat I’d make to you tyranny comment; during WWII the U.S. did treat Japanese-American Citizens with a great amount of tyranny when they sent them all to internment camps for nothing more than being of Japanese descent.

  2. I’m not surprised at the new ruling. I didn’t buy one because it seemed obvious that eventually they would consider the gun to be an SBR.

  3. For installation, do you remove the foam cover from the buffer tube before sliding the brace on, or is the “1.0 – 1.2″ dimension include the foam?

  4. I have both the SB15 and the SB47 braces on my AR and AK pistols. I have had reconstructive surgery on my strong side hand and these devices are a real game changer. It takes a bit of getting used to but I am very happy with these braces. I’m just thankful that Mr Bosco designed these braces. I am also thankful to Sig and Century for producing them. No matter how you use yours just remember the original intent.

  5. where can I order 1 ? do any large distributers carry them in stock ? are they only available through SIG ? thank you

  6. I own the SB47 on my Yugo M92 Pistol. It’s a fantastic product. One thing AK owners need to know about the example that was used with the side folding AK pistol; follow up with the ATF before mimicking this process. Before Century made their version of the SB15 for the AK, a question was sent to the ATF regarding putting a new rear trunnion to fit an AR buffer tube in order to use the stabilizing brace. The response back was that since a buffer tube is not part of the operation of an AK, this method would than classify the AK as an SBR. Just be smart! When you get the brace, print multiple copies of the letter from the ATF stating that the brace is legal and keep with you!

    1. Another practical use is as a vehicle gun. Most states do not allow the loaded carry of long guns inside vehicles. An AR or AK pistol can legally be carried loaded inside a passenger compartment by those who possess concealed weapons permits since they’re considered pistols. Of course, be sure to comply with magazine capacity limits and limitations on threaded barrels or bayonet lugs in prohibited locales.

    2. Better check your state laws on that first, I know for a fact that in South Carolina the CCW law puts a dimensional restriction on any handgun of “12 inches on is longest dimension. Therefore, AR pistols do not meet the requirement.

  7. Looks like it might be a good way to make a compact bug out bag gun with a bit more versatility than a standard handgun while being less obvious than one with a full length barrel.

    The only issue that I would see with it is that it requires the ATF to keep their word to remain legal. With the recent (and not so recent) activities of the ATF, that is not an expectation that I would be willing to risk multiple years of my life on. The recent armed raid on Ares Armor for nothing other than to obtain their customer list that required an assistant US Attorney to perjure himself on a warrant request is just one example as to the lawlessness of the agency. The use of a heavily armed SWAT team to enter the premises instead of simply walking in during normal business hours and presenting a court order for the confiscation of the supposedly illegal unfinished AR receivers is a clear indication of the rogue nature that the agency has taken in the last two decades.

  8. Looks like a great innovation! We’ll be watching the SB15 to see how it performs in the market. But my first impression is that it’s a winner.

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