April 24, 2019
By James Tarr
The FN 509 is one more pistol whose existence is due in whole or part to a manufacturer attempting to win the military’s Modular Handgun System (MHS) contract. The SIG P320 won the contract, and as a result, most of the other designs that were submitted for this competition are being released for sale commercially in one form or another. The American consumer is the big winner here.
The FN 509 could be said to be a slightly altered variant of the FNS striker-fired pistol tweaked to meet the military’s MHS criteria. The first commercial variant of the 509 was a simple, sturdy, duty-size black pistol. On the other hand, the 509 Tactical is nearly identical to FN’s MHS pistol submission—in fact, the only difference is the finish on the slide.
The military contract called for a flat dark earth pistol, so right now you have your choice of a tan 509 Tactical...or a tan 509 Tactical. The military slide finish was some sort of über-secret, DoD-restricted FDE (probably involving a reduced IR signature), and what you’ll find on the slide of the 509 Tactical is a tan physical vapor deposit (PVD) finish.
The slide and the polymer frame are two different colors. The frame is basic tan, and the slide is a darker bronzish hue. This was done for two reasons. One, the two-tone effect looks cool, and two, matching colors on a metal slide and polymer frame is impossible unless you do some sort of paint coating like Cerakote, and FN didn’t want to go that route.
This is a polymer-framed striker-fired 9mm, as is seemingly just about every other new pistol these days. And because it was built for a military duty-pistol submission, this is not a small gun. Sporting an extended threaded 4.5-inch barrel, the 509 Tactical is 7.9 inches long and 5.75 inches tall.
With an empty magazine in place, the manufacturer says the pistol weighs 27.9 ounces. My scale confirmed this, but it felt heavier than that to me.
This is a suppressor-ready pistol, and in addition to the threaded barrel, you’ll see tall night sights. The slide also has the ability to mount a mini red dot optic. More on that later. The barrel has a common 1/2x28 thread pattern.
With this pistol you get a lot of extras. Included are one flush 17-round magazine and two extended 24-round magazines, mounting plates and hardware to attach just about any brand mini red dot to the slide, two backstraps (flat and arched), a cable lock and an excellent nylon carrying case. Not coincidentally, the 24-round magazines are roughly the same length as the slide of the 509, the thinking being that if you can carry the gun, you should be able to carry a magazine of the same length.
If you haven’t been paying attention and FN is just some European gun company to you, let me quickly update you. FN has been around since 1889, and it made its bones supplying firearms to the world’s militaries.
In fact, the MHS contract seems to be one of the few recent U.S. military weapons contracts it hasn’t won. Currently, FN makes the M240 and M249 machine guns for the U.S. military as well as most of the M4 carbines, in addition to other specialty weapons. It is a Belgian company, and in order to land U.S. government contracts, FN had to produce guns here. The 509 is produced in its Columbia, South Carolina, factory, which opened in 1981.
Every feature you might want on a modern pistol you can find on the 509 Tactical. It sports ambidextrous steel magazine and slide releases. The magazine release is large and checkered. On the slide you’ll note the slide serrations are the more aggressive flat-bottomed type, and you also get forward cocking serrations.
The magazine well opening in the frame is nicely beveled. The frame has three different types of agreeably aggressive checkering—from fine stipply texturing under your thumb to 20-lpi checkering on the sides of the frame to a kind of sawtooth-like pattern on the frontstrap and backstrap. The dust cover offers a four-slot Picatinny rail to mount a light, a laser or a combo unit.
As I mentioned, the 509 is a tweaked—some would say improved—version of the FN FNS. Compared to the FNS, this pistol has more aggressive texturing and slide serrations and a larger extractor.
And since the contract called for it, it’s a modular pistol, and the “frame” is actually a polymer shell with the steel chassis pinned into it. The serial number is visible underneath the accessory rail, where a hole is cut into the polymer to reveal the serialized steel chassis inside. Unlike the SIG P320, the steel chassis inside the 509 is not meant to be an interchangeable part swapped between grip shells.
The 509 has four safeties, although only one of them (the trigger safety lever) is externally visible. The other three are a striker block, a drop safety and a trigger disconnect safety.
The muzzle’s thread protector has an internal O-ring to provide some resistance so it doesn’t loosen and fall off under recoil. One note on disassembly of the 509 Tactical: You’ll have to take the thread protector off the muzzle to remove the barrel from the slide. The outside diameter of the thread protector is larger than the hole in the slide.
You will also have to pull the trigger to remove the slide from the frame of the pistol. If that thought fills you with dread and keeps you up late at night worrying, I’d suggest reviewing the four basic rules of safe gun handling.
I mentioned this pistol has tall night sights, but that’s not the whole story. The front sight is dovetailed into place, and there is a highly visible white ring around the tritium insert. The rear sight has tritium inserts on either side of a sizeable notch but no white outlines.
This is at it should be. The rear sight is a window frame you should be looking through, not at. The rear sight is protected by some pretty beefy steel wings, and if you look closely, you’ll see those wings are all one piece with a removable plate.
Red Dot Mounting
Unscrew the plate via the two Torx screws using the provided wrench and you can then proceed to mount a mini red dot sight to the slide using one of the many adapter plates supplied with the pistol. (It’s worth noting here that the FN FNP 45 Tactical, introduced about 10 years ago, was the first production pistol to be mini red dot compatible.)
Perusing the 509’s manual will inform you that using various combinations of provided adapter plates, inserts and screws, you can mount nine different red dots on the slide: Leupold DeltaPoint Pro; Trijicon RMR; J-Point; Docter; Vortex Venom, Viper and Razor; C-More STS2; and Burris FastFire.
Unlike most of its competitors, with the FN 509 all of the optics mount directly to the slide for maximum robustness. The adapter plates fit the optics to the slide, but the mounting screws go from the optic, through the plates, directly into the slide. The larger rear adapter plates are polymer, the forward plate with the index posts is steel, and there is a rubber O-ring between the forward plate and the top of the slide to absorb impacts to the optic body.
The specs for the MHS contract read like a wish list of all the cool new things pistol manufacturers have been experimenting with the past decade or so in addition to proven technology such as sound suppressors and night sights. I don’t know which surprises me more, the comprehensive modern features the often-behind-the-curve military asked for with the MHS or the fact that more than one manufacturer stepped up with a product that gave the military everything it asked for.
One of those “cool new things” is the red dot aspect. This is the new fad, and technology has improved so much that it is now possible to mount onto carry-size guns red dots that are both small enough to conceal and tough enough to handle recoil. If your eyes are aging and you’re having trouble getting the front sight into focus, a red dot is definitely a viable alternative. And red dots are great for training new shooters because they are simpler to learn on than traditional iron sights.
Red dots may help you shoot more accurately, but exhaustive studies have shown that they are slower to use than iron sights for everyone but the most expert shooters, especially inside a normal defensive distance of 10 yards. Speed is more important in a defensive situation than an insignificant improvement in accuracy.
However, lighter, crisper trigger pulls have been shown to vastly improve both accuracy and speed for all shooters, regardless of ability, and the main thing handicapping this pistol is its seven-pound trigger pull. Factory specs call for a 5.5- to 7.5-pound pull, but most 509 Tactical samples I’ve laid hands on had pulls near the top of that range. A seven-pound trigger pull isn’t worst in class for a striker-fired pistol, but it’s close.
Let’s not get lost in the weeds, though. A seven-pound trigger pull works just fine for shooting bad guys across the room or across the hood of your car. As do iron sights. But for those of you wanting more from your gat, many aftermarket accessory manufacturers seem to have jumped on the 509 bandwagon, including Apex Tactical. For this article the company sent me an Action Enhancement Kit for the FN 509 that features a replacement trigger, trigger bar and sear and lowers the trigger pull to approximately 5.5 pounds.
When it came time to throw lead downrange, I met up with fellow Handguns scribe Pat Sweeney at the range because he had a large selection of 9mm suppressors on hand. I chose to mount the Blackhawk Mini Boss on the 509 Tactical to test one of my working theories—namely that suppressor sights are generally unneeded. The Mini Boss is short and fat, so fat that you cannot see the tall suppressor sights of the 509 over the body of the suppressor.
However, this shouldn’t matter if you are shooting your pistol with both eyes open, as you should be. When you shoot with both eyes open, your brain superimposes the front sight on the target. So as long as you can see the front sight in contrast to the body of the suppressor, you do not need tall suppressor sights. The big white ring on the front sight of the 509 Tactical works great for this.
I was able to hammer steel plates out to 20 yards easily even though the Blackhawk suppressor prevented me from actually seeing the sights on the target with my dominant eye. I understand tall sights are cool, and some people want to be able to see the sights over their suppressor no matter what. Just be aware that when push comes to shove you don’t necessarily need them.
This is a big pistol chambered in 9mm, which means it is very soft shooting. It’s actually very fun to shoot, and whether or not you attach a suppressor to the muzzle, you will definitely have a lot of fun punching paper and/or knocking down steel. Matching the Blackhawk Mini Boss with Aguila 147-grain subsonic ammo made for a pleasant shooting experience and was quiet enough to be ear safe.
From its size, I think this pistol would excel as a gun for the bedside table. Clamp a light on the rail and shove in one of the provided 24-round magazines and you’ve got a great “Get off my lawn” pistol with or without a red dot on the slide.
However, perhaps the biggest draw of this pistol for me is this: It’s a piece of military history. It’s the MHS that could have been—and that some will argue should have been. Again, apart from the finish on the slide, the 509 Tactical is identical to FN’s MHS submission to the military, and that’s what makes this pistol special.FN America 509 Tactical
Type: striker-fired semiauto
Barrel: 4.5 in.
OAL/Height/Width: 7.9/5.75/1.35 in.
Weight: 27.9 oz.
Construction: tan PVD-finished steel slide, polymer frame/grip
Sights: white outline tritium front, tritium rear
Trigger: 7 lb. pull (measured)
Safety: trigger lever, striker block, drop and trigger disconnect
Manufacturer: FN America, FNamerica.com