FN 'Big Bore' Striker-Fired Pistols (510 and 545 Tactical): Everything You Need to Know

FN adds 10mm and .45 ACP variants to its 500 series of striker-fired pistols. Meet the 510 and 545 Tactical.

March 07, 2023 By Brad Fitzpatrick

The 509 earned a lot of attention and impressed many shooters following its participation in the U.S. Army’s Modular Handgun System competition. The 509 Tactical was reviewed in Guns & Ammo’s September 2018 issue and was selected by several law enforcement agencies as a duty sidearm, including the LAPD in 2021. FN’s striker-fired flagship in 9mm has received similar acceptance in the commercial market, as well.

In 2023, the 500-series expands to include the 510, 10mm auto, and 545 in .45 ACP. In addition to bigger bores and beefier frames, both pistols boast impressive magazine capacities: 15 and 22 rounds for the 510, and 15 and 18 rounds for the 545. Of course, there are also 10-round magazines for areas of the country with capacity restrictions.

FN is hardly the first company to release a striker-fired 10mm pistol in recent memory. Both Springfield Armory and SIG Sauer were quick out of the gate, for example, but FN’s addition of a high-capacity .45 is a bit of a surprise. Despite it’s inauspicious start at life back in the 1980s, the 10mm has steadily picked up steam in the pistol market. Today the 10mm is a juggernaut, but the classic .45 has lagged in recent years. Still, it’s good to see FN launching the optic-ready 545 alongside the new 510 model.

FN 510 Tactical Pistol (Mark Fingar photo)

FN is not a brand prone to flights of fancy. The company isn’t known for changing color schemes, grip textures or capacities and launching “new” pistols. Instead, FN creates platforms, such as the 509, and then makes revisions of the design to meet the changing needs of shooters. The 510 and 545, then, are simply evolutions of the 509, and as such they remain similar to the original. Both the 510 and 545 are striker-fired pistols that feature CNC-machined stainless-steel slides with angled front and rear slide serrations. Both the 510 Tactical and 545 Tactical feature three-dot, metal, suppressor-height sights with tritium lamps installed for around-the-clock illumination. The rear sight’s dual tritium lamps are recessed to cut glare, while the flat face of the rear sight is a ledge to allow for one-handed cycling. A large white ring surrounds the tritium lamp in the front sight, which calls the shooter’s attention when aligning to the target.

The FN 510 and 545 Tactical models feature Trijicon’s three-dot, suppressor-height night sights. They are flanked by the protective ears of the optic-cut coverplate. (Mark Fingar photo)

Both the 510 and 545 Tactical feature slides that are cut to accommodate reflex optics. FN patented its Low Profile Optics Mounting System. Each pistol comes with a blister pack that contains the necessary hardware for mounting reflex sights, as well as a Torx/hex wrench required for removal of the slide’s cover plate and to secure the optic to the slide. The cover plate fits tightly against the slide, and there are two protective “wings” that guard the flanks of the rear sight.

Like the 509, both the 510 and 545 come with FN’s heavy-duty conical striker. It’s a robust and reliable design, as is the .2-inch-wide hardened steel extractor that serves double duty as a loaded chamber indicator.

While the 4 1/2-inch cold hammer-forged barrel is a bit shorter than its contemporaries, the FN 510 and 545 Tactical models include .578 x28 threads for attaching a suppressor. (Mark Fingar photo)

Both the 10mm 510 Tactical and the .45 545 Tactical come with cold hammer-forged barrels with target crowns and polished feed ramps, as well as chambers optimized for accuracy. The barrel is threaded .578x28 for attaching compensators or suppressors. Total barrel length is 4.71 inches and both pistols are available with a matte black or FDE PVD finish.

FN uses a polymer frame very similar to the 509 for both the 510 and 545. There’s aggressive texturing on the frontstrap and removable backstrap. On the flat sides of the grip surface, there’s additional and less-aggressive texturing. Molded recesses just behind the trigger on the left and right side of the frame received more mild micro texturing, and the grip angle is similar to the 509. The two interchangeable backstraps allow the shooter to adjust the rear profile of the grip based on hand size, but both backstraps work to position the hand high on the grip just under the beavertail for excellent control. A mil-std M1913 accessory rail is located on the dust cover. A steel chassis rides inside the frame, and the interior of the pistol is free from burrs and machine marks.

Texturing on grip — The familiar texturing of the 509 series carries over to the 510 and 545, including an optional backstraps that allows the shooter to personalize control and coverage around the grip. (Mark Fingar photo)

All 500-series pistols have a straightforward control layout with slide stops, magazine-release buttons, and a rotating takedown lever. Both the slide stop and oval mag-release button are ambidextrous, so there’s no need for lefties to reconfigure the pistol before operating. Takedown is fast and simple, too, and once the gun is fieldstripped, you’ll find a dual captured recoil spring and clean machine work inside the slide.

FN 500 series pistols come with a two-piece trigger assembly where the lower half of the trigger face acts as a safety, much like a bladed trigger. The wide trigger face isn’t flat like some other guns, but it is smooth and predictable. FN 509 pistols are listed as having trigger weight between 51/2 and 7.7 pounds. The 545 measured 51/2 pounds on average for me, and the 510 at 5.9 pounds. I don’t know if sub-six is the new standard for 500-series pistols or these early production guns were worn in by shooters at the factory. (Both the 510 and 545 samples I tested had been fired, though neither appeared to have serious wear). These pistols have the best triggers of any FN 500 guns I’ve tested yet.

Shooting the FN pistol — (Mark Fingar photo)

Both the 510 and 545 measure 8.3 inches long, 11/4 inches wide at the frame, and 1.45 inches wide at the slide stop. The weight for the 545 measured 1 pound, 15 ounces (unloaded), while the 510 weighed exactly 2 pounds.

The 510 Tactical comes with one 15-round flush-fit magazine and one 22-round extended mag. The 545 Tactical includes 15- and 18-round extended-capacity magazines. Both guns are available to ship with two 10-round magazines, as well, for those in restricted areas.

The retail price for both pistols was set at $1,139. That’s higher than the Springfield XD-M Elite OSP 4.5-inch 10mm ($653) and the SIG Sauer P320 XTen, which costs just shy of a grand. The XTen has a longer 5-inch barrel when compared to the FN 510 Tactical, and is an ounce heavier, but the 15-round capacity of the XTen and 16-rounds in Springfield’s 10mm can’t match the FN’s cavernous 22-round mag. Neither the Springfield or SIG Sauer come with a threaded barrel standard. Rather, the 545 seems to be in a class by itself. The FN 545 Tactical is truly an outstanding option if you like big bores. With a base capacity of 15 rounds, no one can complain that the .45 has a lack of cartridge capacity.

At the Range

FN’s pistols are predictable, and I mean that as a compliment. The actions are smooth, the fit and feel is excellent, and these guns are built with premium components. The external extractor sits in a very tight groove on the slide, but it fits perfectly with no issues. The extractor takes a large bite on the case rim and holds on tight, ensuring that even the most stubborn rounds get the boot.

For testing, I mounted a Leupold DeltaPoint Pro ($450, leupold.com) to the 545 and 510. The DeltaPoint Pro is a tall sight that requires the longest screws included with both 510 and 545 packs. Many “suppressor height” pistol sights won’t co-witness with this optic, but the Trijicon sights are visible through the bottom of the window. It’s not what I would describe as “lower-third” co-witnessing, but I was able to use them. If the Leupold functions with the sights, then most other optics should, too.

Leupold DeltaPoint Pro optic — The Leupold DeltaPoint Pro is the tallest optic you can mount to these guns. Still, the Trijicon sights still peek through. (Mark Fingar photo)

The popularity of slides with optic cuts has prompted some pistol manufacturers to treat iron sights as an afterthought. Not FN. You could probably pound nails with these sights! (I didn’t try.) The sight layout is excellent. The oversized white dot on the front grabs the shooter’s attention and helps one to focus. Both the front and rear sights are strong enough for one-handed cycling in an emergency, too.

Every machine cut to the FN’s slide was purposeful. It is obvious. Carry cuts and angling at the top of the slight keeps weight down and makes it easier to reholster the gun. These also give this pistol a sophisticated look. Aesthetics don’t punch holes in the 10 ring, but if you’re dropping a grand for a polymer pistol it should shoot well and look good. Both the 510 Tactical and 545 Tactical were purpose built, which is why the do not appear gaudy.

I don’t like cheap sights, but I really hate cheap magazines. Fortunately, the FN’s metal magazines are very good. Magazine spring weight is heavy enough to keep rounds moving up the line, but good luck topping off either the 510 or 545 extended-capacity magazines at the range without a mag loader on hand!

The slide is optic-cut with one of the best optic-mounting systems on the market. It includes adapter plates, various screws and a wrench to accommodate nearly any red-dot sight. (Mark Fingar photo)

The slide stop and magazine releases are large enough that they are easy to operate, too, but the grip texturing is a bit rough. I’ve learned that it’s more comfortable to wear gloves when working with 500 series pistols for long shooting durations; I suggest you do the same. FN favors the aggressive grip design, but I prefer something a little less aggressive for carry, sometime more like the texture found on the competitions’ models. Still, aggressive texturing is a hallmark of the FN brand.

Mounting optics on these pistols was easy, but be warned: When you open that blister pack and allow the adapter plates, screws and O-rings free, you may never find them again! I suggest separating the different components into bags. It’s not hard to mount optics on either the 510 Tactical or 545 Tactical unless, of course, you lose the parts you need.

Inside the polymer frame is a familiar action assembly. The steel frame and slide rails are replaceable. They were engineered to minimize friction, wear and corrosion. (Mark Fingar photo)

With the Leupold DeltaPoint Pro in place, and a crate of .45 and 10mm ammo loaded up, I went to the range on a rainy afternoon to test the two new members of the FN lineup. First, the 510 Tactical. It managed a test-best group of 1.6-inches with Speer’s 200-grain self-defense Gold Dot load at around 1,050 feet per second (fps). The 545 Tactical, ironically, produced a test-best five-shot group that measured the same 1.6-inches for five shots at 25 yards! Unbelievable. Both pistols produced multiple five-shot groups between 1.8 and 2.2 inches at that distance. Overall accuracy was slightly better with the 545, and that may have been a result of the marginally lower trigger weight. I noted both guns feature grips that are angled to keep the hand high and transfer recoil energy effectively through the shooter’s arms and shoulders.

FN magazine — With magazines having 15 or 18 rounds, the FN 545 Tactical strikes down the old complaint of pistols chambering .45: Low capacity. Col. Jeff Cooper would have approved. (Mark Fingar photo)

Off the bench, I tested both guns using my basic Bear Drill; turn, draw the pistol, fire one accurate shot in less than 1 second. It’s a simple and accurate representation of what you can expect during a bear charge. Then, Mozambique drills. Both guns offered short trigger resets for fast follow-up shots, provided shooters do their part.

The internal chassis strengthens the dustcover rail. A window provides visual access to the pistol’s serial number. The dot matrix to the right is the serial number code for inventory scans. (Mark Fingar photo)

Not surprisingly, the 510 and 545 were very reliable. There was only one malfunction: A failure-to-feed with one Blazer 180-grain FMJ 10mm round. Retracting the slide to relieve pressure on the nose of the bullet and then releasing the slide allowed the gun to go into battery.

Overall, I found that these guns were well-built. That keeps with the FN 500-series’ reputation. Whether defending yourself against a two- or four-legged predator, hog hunting, or simply hammering steel in the backyard, you can count on these guns to make an impact every time.