An AR 15 Pistol is a ‘pistol’ variant of the AR-15 rifle platform, featuring a barrel shorter than 16 inches.

Unlike Short-Barreled Rifles (SBRs), AR Pistols are not subject to NFA regulation, though there are additional restrictions to remember when building a pistol. For example, AR 15 pistols cannot feature a rifle stock or vertical grip, but a ‘pistol brace’ may be used for additional support with the user’s dominant arm.

Otherwise, AR pistols are entirely compatible with standard AR-15 parts and components.

In appearance, AR15 pistols and AR15 SBRs share many similarities, but there is a fine legal separation between the two classifications.

AR 15 SBRs are short-barreled rifles, defined by the National Firearms Act. In essence, it’s a standard AR with a barrel length less than 16”. To purchase an SBR, you must complete a Form 1 or Form 4 with the ATF, undergo lengthy vetting, and submit detailed personal information before paying a $200 tax stamp.

AR Pistols are, by legal definition, the same as any other pistol. You do not need to complete NFA registration for an AR pistol, and their agility and mobility in close-quarters make AR pistols a top choice for home defense. You also have the same restrictions on attachments that you would have on a pistol: no stocks or vertical foregrips. If you put a stock on an AR pistol, you’ve manufactured an illegal, unregistered SBR—a federal felony with serious repercussions.

Disclaimer

The information contained in this article is for informational purposes only. This content is not intended as legal advice and should not be taken as such. Those wishing to obtain more information about the construction of an AR 15 Pistol should contact the Bureau of Alcohol, Tobacco, Firearms and Explosives directly.

With that said… Yes. In most states, AR15 pistols are perfectly legal. They adhere to the same laws as any other pistol. That said, these laws can be somewhat complex, so it’s important that you do extensive research both on federal law and your local/state laws to confirm a pistol’s legality. Federal law has some strange intricacies as well. For example, if your pistol’s overall length measures over 26” (not counting muzzle device), it may be able to have a vertical grip because it classifies as a ‘firearm’ instead of a ‘pistol’. This is because the legal definition of pistol considers concealability, which is partially defined by overall length.

That said, if you want to play it safe, DO NOT USE A VERTICAL GRIP ON A PISTOL. The ATF has previously stated that angled foregrips and handstops are fine, but their views can change quickly. You’re better off running a plain handguard than risking it with a foregrip that sits on the border of legal.

Pistol braces can look quite a lot like regular rifle stocks. However, their intended use is to be mounted on your forearm as you fire the “pistol” with one hand.

Of course, many pistol braces are comfortable enough to be shouldered and fired like a rifle. Although shoulder firing is not their ‘intended’ use, many users still do so. You can find fantastically comfortable options from SB Tactical, Foxtrot Mike, Shockwave, Strike Industries, Sig Sauer, and CMMG.

AR style pistols excel in home defense situations, truck gun use, competition shooting, and backpack guns for hiking or hunting. This is because of their compact size, low weight, durability, and ease of use.

In short, AR pistols give you the advantages of an SBR without wading through the mire of paperwork and regulation associated with NFA items.

AR pistols encompass a broad range of sizes and calibers.

That said, the main advantage of an AR pistol is its short barrel, so most users will tailor their selection to get the most out of that compact size. Most AR pistols chambered in 5.56x45mm NATO will feature a barrel length between 7.5” and 12.5”, though they can be much shorter when paired with specialized low-velocity cartridges like .300 Blackout or pistol calibers.

An AR-15 chambered in a traditional pistol caliber (9mm, .40 S&W, .45 ACP, etc.) may also be called a ‘Pistol Caliber Carbine’ or ‘PCC’.

Since pistol cartridges do not benefit from long barrels, many PCC-owners will build their PCC as an AR15 pistol. PCC Pistols usually follow the same regulations as other AR15 pistols, though their proprietary nature means reduced parts compatibility with standard ARs.

Some of the most fun you can have at the range is with a 9mm AR PCC with a 5” or 7” barrel. You have unmatched mobility and acquisition speed. The range on a 9mm AR is good out to medium range, and most PCC pistols weigh under 5 pounds, so you can carry all day long. Just remember not to put a vertical foregrip or rifle stock on it without your tax stamp.

.300 AAC Blackout is a low-velocity, high-weight cartridge optimized for AR15s with short barrels. The projectiles are wider (.30” vs .22”) and heavier (110-220gr vs 55-77gr) than standard 5.56. This means 300 Blackout has a shorter effective range, but it delivers more mass on target. With a heavier bullet, you preserve your terminal ballistics at lower velocities, so you can get adequate performance from ultra-short barrels. With .300 Blackout, you can even have a 5” barrel without over-gassing or reliability issues.

Other benefits of .300 Blackout include parts compatibility and suppressed noise ratings. With .300 Blackout, you can use many of the same parts and components as standard 5.56x45 pistols. You can even use the same magazines as 5.56. If you pair 220gr .300 Blackout with a quality suppressor, you can get into the 120 dB range, making it one of the quietest cartridges available to the AR platform.

The only downsides are the increased cost of ammo, reduced range, and slightly heightened recoil impulse.

Yes, 5.56x45mm NATO remains the most popular caliber option for AR15 pistols.

There are some downsides to 5.56. You won’t have the same range or terminal ballistics as a full-size rifle, since 5.56 ball ammo relies on ball ammo, but a quality 77gr bullet can make up for much of the performance loss. AR pistols will also be much louder and gassier than rifles, and the recoil impulse may be very slightly larger.

However, these are all marginal trade-offs compared to the handling advantage of a short barrel. If you’re shooting from a vehicle or a tight hallway, AR pistols will be substantially more effective than a full-size rifle. Your AR pistol will also be somewhat lighter, and the balance will make it easy to carry and shoot on the move.

If you stick to a 10.5-inch or longer barrel with quality defensive ammunition, an AR pistol can achieve terminal ballistics comparable or superior to a full-size rifle with standard XM193. You’ll have an effective range to 300 yards, which is plenty for almost any domestic purpose.