After a decade and a half of near-constant combat, the U.S. Army has decided to replace the Beretta M9 pistol it adopted back in 1985. In mid-2015, the Army issued a request for proposals (RFP) soliciting manufacturers for pistols meeting its criteria for the new Modular Handgun System (MHS). The purpose of the new pistol, codenamed the XM17, would be to “provide warfighters with a best-value system that features increased lethality, increased accuracy, improved ergonomics and a higher degree of reliability over legacy handgun systems.”

The prestige of being named the winner is undeniable. However, the commercial aspect of this equation is what drives most manufacturers to invest in research to develop a weapon for the RFP and subsequent trials. And the Army had a long list of specifications that the XM17 had to meet to be considered for adoption. Understandably, most companies didn’t have an off-the-shelf solution to the criteria posed, necessitating the development of new pistols. One of those companies is FN.

FN’s Legacy

FN has a long and rich history of supplying weapons to the United States military. From the M16A4 to the M249 SAW, to the 5.56mm and 7.62mm SCAR systems, to the MK19 belt-fed grenade launcher, FN has provided several quality weapon systems for our fighting men and women. In addition, the company was already manufacturing a polymer-framed, striker-fired pistol—two of the major criteria for the next XM17. The FN gun developed to meet the specifications of the Army’s RFP is now known commercially as the FN 509.

The starting point for this new pistol was the FNS Compact—a striker-fired, polymer-framed pistol. This gun provided the basic architecture. During its development, FN made several changes to the frame, barrel and slide. FN redesigned other components to meet the military requirements for increased reliability, accuracy and ergonomics.

Not wanting to place all of its eggs in one basket, FN also started an extensive survey looking for feedback that would help the company develop the FN 509 as a duty gun for law enforcement. Ergonomics tended to be one of the top considerations for both military and police agencies. Given the size differences among various personnel, the ability to provide one gun that is comfortable to use for those with small and large hands alike was a daunting challenge.

For All Warriors

My evaluation sample of the FN 509 came with three different backstraps. Interested in interchanging them? Simply push out the retaining pin, slide the backstrap off the frame, install a different one and reinstallthe pin.

The sides of the grip frame feature sharp pyramid-style checkering to provide a rock-solid grip even when wet. Above the pyramidal checkering is a texture similar to skate tape, while the front- and backstraps have what FN calls “Dragon Scales.”

These three different styles of texturing should provide an excellent grip even when used with gloves.

There are a number of other frame features that I found particularly favorable. The tang or beavertail area of the gun has a great design. It is proportioned to protect the hand from being “bitten” by the reciprocating slide. Subtle polymer fences around the slide and magazine releases, as well as the takedown lever, prevent inadvertent activations of any of these controls. FN also elongated the triggerguard, making the pistol safer to shoot while wearing gloves. The extra-large triggerguard also presents an excellent opportunity for holster makers to use the forward portion of the guard opening to create a friction lock.

The frame’s dust cover sports a Picatinny accessory rail. The rail allows for any number of accessories, including lights, lasers and combination units.

The slide’s cocking serrations are deeper and cover a great deal of surface area, both fore and aft, to provide the user a more positive grip when charging the chamber or unloading the pistol. FN engineers also included an external extractor that pulls double duty as a visual and tactile loaded-chamber indicator.

FN has designed the 509 to be fully ambidextrous, and it features bilateral slide stop levers and magazine releases. Looking through the 509’s owner’s manual, additional models may feature a manual safety. My sample did not possess such a safety.

FN engineers did, however, manage to include four passive safeties in the 509’s design. There is a striker block that prevents the striker tip from protruding through the breech face unless the trigger is pulled. The drop safety prevents the sear from moving out of engagement with the striker unless the trigger is deliberately pulled, and the trigger disconnect safety is actuated when the disconnect cam is pushed out of alignment with the sear, preventing it from releasing the striker. This prevents the gun from firing when the slide is out of battery.

Looking at the pictures, you’ll see what appears to be a pin at the middle of the trigger’s profile. Like many of the other current generation of striker-fired guns, the FN 509 has a trigger safety that blocks rearward movement of the trigger unless it is purposefully pulled. This prevents inertia movement of the trigger if the gun drops on its muzzle.

The trigger pull on my test sample weighed in at about 7 pounds. The spec sheet for the 509 lists the trigger pull as ranging from 5.5 to 7.5 pounds. This pull weight likely was specified by the Army. It will likely find favor with assorted police agencies that would view a lighter trigger pull as a liability.

FN has quite a reputation for its barrels. The 509 uses a cold-hammer-forged barrel with a polished chamber and feed ramp. In an unusual move, however, FN machines the barrel with a recessed target crown—not unlike what we would see on a high-dollar precision rifle. While FN literature claims that this helps each bullet stabilize as it leaves the muzzle, I think the best benefit is that it protects the rifling in the event the pistol drops.

Finally, we come to the disassembly process. Any military weapon needs to be easily disassembled. The FN 509 is no different. Unload the gun and remove the magazine, then lock the slide to its rearward position. Now rotate the disassembly lever downward. Grasp the slide, depress the slide stop and ease the slide forward. With the pistol pointed in a safe direction, pull the trigger and pull the slide and barrel forward off the frame. Turn the slide upside down and remove the recoil spring system. The barrel can now be lifted from the slide. This is as far as the manual recommends for disassembling the gun and should be enough for routine maintenance and cleaning. Reassembly is in the reverse order. It is an uncomplicated process. It can be performed in complete darkness without much of a problem.

FN 509 Range Test

Before I hit the range, I must admit that I was concerned that such a heavy trigger pull would make group shooting nearly impossible. But I was wrong. I set up targets at 25 yards and fired five-shot groups using a DOA Tactical shooting bench and a Millett BenchMaster for support.

As you can see in the accompanying table, the trigger pull didn’t really affect my ability to print some very nice groups with the FN 509. DoubleTap’s 77-grain hollow points produced the best five-shot group of the day, which measured just over an inch. This round also produced the most energy of any of the loads I tried. Because of the projectile’s light weight, the felt recoil of this round is extremely light. Overall, the FN 509’s accuracy was impressive. The average group size of the six ammunition types I tested was just 1.5 inches.

During my short evaluation, I fired about 300 rounds and had no failures of any sort. Despite the differences in bullet weights, nose profiles and overall lengths, the FN 509 never choked.

I personally found the FN 509 to be well made, reliable and very accurate. If your needs include a lightweight, high-capacity, semi-auto handgun, make sure to give the brand-new FN 509 a look. I’m sure you’ll be impressed. I know I was.

Caliber: 9mm

Barrel: 4 inches

OA Length: 7.4 inches

Weight: 26.9 ounces (empty)

Grip: Polymer

Sights: Three-dot luminous

Action: Striker-fired

Finish: Matte black

Capacity: 17+1

MSRP: $649

For more information, visit

This article is from the November/December 2017 issue of “Combat Handguns.” To order a copy and subscribe, visit

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