Final Thoughts

As muzzle brakes go, the Pro Comp is a good one, even for this short rifle. Still, my preference would remain a forward-facing brake on anything designed for use in close quarters or confined spaces. Granted, this 12-inch barrel is not really that short, but you are still using it in close proximity to others or inside, the sweet spot for an AR pistol.  Firing from inside the vehicle still sent quite a bit of blast to the sides—blast diverters fix that, especially shooting subsonics.

With the longer (for an AR pistol) 12-inch barrel length you give up a bit of convenience and concealment but gain optimal bullet performance and reliable funtioning, and the FN 15 proved extremely reliable throughout testing.

FN America’s FN 15 is very mil-spec, pretty much an M16 without the happy switch (or ability to add one) using a single-side safety, magazine release and charging handle.  At $1599 it’s neither over-priced nor entry level, but it would have been nice to see at least an ambidextrous charging handle, as it really helps with operation. 

In an ever-growing market, FN America has added another solid choice for a rifle-caliber pistol. Accurate, reliable and built to last, it provides simple and effective features at a reasonable price. If you’re in the market for an AR pistol, this one should be on your short list, maybe at the top. See the FN 15 lineup at your nearest dealer, or for more information, contact FN America; Tel.: (703) 288-3500; E-mail: [email protected]; Web:


Caliber/Gauge: 300 BLK

Receiver Set: FN 15

Barrel: 12 inches 

OA Length: 28.6 inches 

Weight: 5.65 pounds

Sights: Flat Top /Accepts rail-mounted sights and optics.

Stocks/Grips: Magpul Grip/Midwest Industries Hand Guard

Pistol Brace: SB SBA3 Pistol

Action: Semi-Automatic/Rotating Bolt/Direct Impingement

Finish: Anodized

Capacity: Accepts AR15 based 5.56mm or 300 BLK magazines

Price: $1599.00


Load                                            Velocity                      Group Size

Hornady 190-gr. Sub-X                 1,030                          0.75   Inches

Sig Sauer 220-gr. OTM                  1,000                         0.70   Inches

Lehigh Defense 194-gr. CE           1,050                          0.80   Inches

Black Hills 125-gr. TMK                 2,170                          1.00   Inches

Sig Sauer 125-gr. Match                2,100                          0.75   Inches

Barnes 110-gr. TAC-TX                  2,300                          0.90   Inches


Bullet weight measured in grains, velocity in feet per second with a MagnetoSpeed V3 chronograph. Accuracy in inches for three five-round groups fired from 25 and 50 yards using a bag as a rest standing behind a bench.