FN recently debuted the third generation of its 5.7x28mm caliber pistol, bringing the curious pistol from the 1990s kicking and screaming into a more modern period. 
We've been testing for the past few months and have a 500-round review. 

Table of Contents
Shooting & Accuracy
Customer Reviews
Pros & Cons
Final Thoughts



The new Five-Seven MRD was announced last June by FN as the MK3, or the third generation of the pistol series. This follows up on the original LE-restricted "Individual Officer’s Model" and USG guns that first appeared while Chumbawamba was on the charts back during the Federal Assault Weapons Ban and the updated MK2 variation that hit the scenes in 2013. 


FN Five Seven USG model
Except for the hard-to-find original Five-seveN model with an elongated trigger guard and no accessory rail, the U.S. Government, or USG model, was the first commercial model of the pistol marketed in the U.S. Note the Fredricksburg, Virginia, stamp on the frame. (Photo: Guns.com)
FN Five Seven MK2
The Five-seveN MK2 was the standard 5.7 pistol made by FN for the past decade. Note the forward slide serrations that set these models apart from older USGs as well as the Columbia, SC, stamp on the frame. MK2s are still available new in the company's catalog as well as on the secondary market. (Photo: Guns.com)


RELATED: Hail the 5.7x28mm Pistol King, the FN Five-seveN MK2


We're not going to get into the whole mystique of the 5.7 NATO round – which was recently standardized by the international defense alliance – as we have done that before. Suffice it to say that the Five-Seven, as its name would hint, was the first pistol on the block to be built to run it, and its standard capacity is 20+1 rounds of the zippy little bottle-necked cartridge, all held in a flush-fit magazine that weighs about as much as an empty Kleenex box.
What the new MRD MK3 brings to the game is the ability to mount just about any micro red dot optic (hence "MRD"), something that was particularly hard to retrofit on previous models, as well as a lot of updates to the pistol's ergonomics. All this in a hammer-fired delayed blowback action semi-auto with a semi-fixed barrel chambered for the spicy little 5.7 round.

FN Five Seven MRD MK3 pistol in FDE
The new FN Five-Seven MK3 MRD, in Flat Dark Earth, because FN. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
The pistol is also available in black, for those five guys who hate peanut butter-hued guns. (Photo: Chris Eger/Guns.com)


Specs (Per FN)

  • Overall Length: 8.2 inches
  • Barrel Length: 4.8 inches
  • Sight Radius: 7 inches
  • Height: 5.6 inches
  • Width: 1.35 inches over surface controls
  • Weight: 25.2 ounces (unloaded)
  • Magazine Capacity: 20+1 



Weight savings, while still having a full-sized pistol with a decent standard magazine capacity, seems to have been number one on the goal list for FN's Five-seveN engineering team. As mentioned above, the unloaded weight of the 1911-sized pistol is just 25 ounces, while its loaded weight, with a Leupold Delta Point Pro red dot installed and 21 rounds aboard, only comes in at 29.8 ounces on our postal scale. 

FN Five Seven MRD MK3 pistol in FDE
Still, make no mistake that this is a full-sized pistol, despite its weight. Keep in mind that I am a big boy that could palm a basketball at age 10. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
The MRD is hand-filling, and, at 8.2 inches long overall, is comparable to the new all-metal FN High Power 9mm in length and height while coming in much lighter. For instance, the MRD hits the scales at 28 ounces as shown loaded with 21 rounds while the High Power is 43.5 ounces with 18 rounds loaded. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
Note the simplicity of the field-stripped pistol, with the recoil spring over the barrel in the same manner as the Walther PP/PPK. Unlike many polymer-framed pistols, the MRD is hammer-fired rather than striker-fired. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
A lot of the weight savings comes via the use of polymers, with the grip frame being polymer, and even the slide sandwiched with a tough polymer outer shell over a steel inner slide. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
A big bonus on the MRD MK3 is that it carries new stippling and textures on the frame as well as enhanced serrations on the slide, trigger guard, and safety selector that update the pistol's ergonomics. Past classic and MK2 models have a much slicker surface texture. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
The other big update is the capability to mount just about any pistol red dot on the market. The polymer cover plate is easily removed to allow access to the steel slide underneath, which is milled and ready for adapter plates. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
FN ships the MRD currently with three interface plates and four different mounting screws to allow out-of-the-box compatibility with Burris FF2/FF3, Vortex Viper/Venom (Docter/Noblex), Trijicon RMR/SCO/SIG Romeo/Holosun 507/Swampfox Kingslayer, and the Leupold DPP/Shield RMS/SMS/Holosun K footprints. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
We went with the Leupold DPP 6 MOA MRD, and the rear Italian-made LPA sight *almost* co-witnesses. European pistol makers just love LPA sights and you see them a lot on CZs and Tanfoglios. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
Speaking of sights, the MRD features an excellent photo-luminescent front sight that pairs well with the adjustable rear. While the front is very high, it would be nicer if the rear were a little taller to ensure lower-third co-witness on more optics. (Photo: Chris Eger/Guns.com)

When it comes to surface controls, the MRD has a left-side-only slide catch and take-down lever. The mag release comes installed on the left side of the frame. Showing its 1990s military roots, the pistol runs a fully-ambi manual safety without an option to ditch it. 

FN Five Seven MRD MK3 pistol in FDE
Rather than being fitted to the rear of the frame to be thumbed on and off with the strong hand, the manual safety lever is best actuated by the thumb of the support hand, something that is just downright weird for most users who have experience with just about any other pistol. (Photo: Chris Eger/Guns.com)


In addition to the manual frame-mounted safety lever, the MRD uses an internal magazine safety. In other words, it cannot be fired without a magazine inserted, even if there is a round in the chamber. 

FN Five Seven MRD MK3 pistol in FDE
Speaking of magazines, the traditional Five-seveN mag is interesting, weighing in at just around 2 ounces when empty. Capable of holding 20 rounds of 5.7 and still flush-fitting into the mag-well, it was class-leading when first introduced and still holds its ground against a lot of competitors today. (Photo: Chris Eger/Guns.com)

In bad news, the MRD MK3 uses different mags than the legacy Five-seveN models due to the redesigned grip on the new guns.

FN Five Seven MRD MK3 pistol mag compared to MK2
The MRD MK3 mag on the left looks almost identical to the MK2 mag on the right. (Photo: Chris Eger/Guns.com)
FN Five Seven MRD MK3 pistol in FDE
They are not interchangeable and the MK2 will not seat and lock into place. (Photo: Chris Eger/Guns.com)

Shooting & Accuracy


The blowback action, soft recoiling round, decent sight radius (augmented by an MRD optic capability), and semi-fixed barrel would seem to make the FN MK3 a hyper-accurate pistol. If only the hammer-fired handgun's trigger was there to help with that. With a 6-ish pound pull (FN lists it as "4.4 - 7.87" which is a large swing) and a half-inch travel before coming to the wall, it is functional but could be a lot better. Again, keep the gun's military roots in mind. 

However, if you are looking for an aftermarket upgrade, Eden Perfection, who already markets MK2 trigger packs and does 4-pound triggers for the same, says they are working on a flat-faced, adjustable, short-reach trigger for the MK3.
While accuracy didn't blow us away – we averaged about 4-5 inch groups firing from the bench at 25 yards with all ammo types and could keep it in the black when shooting rapid strings offhand at the same distance – it is nonetheless very functional. The MRD is not an Olympic competition pistol but it is ready for everything short of that benchmark.|

FN Five Seven MRD MK3 pistol in FDE on range
With the Leupold DPP installed, we could make reliable head shots at 25 yards when braced against the barricade and hit torso-sized (10x12 inch) steel out to 100 yards offhand with a little bit of concentration. It is very flat shooting. (Photo: Chris Eger/Guns.com)

When it comes to reliability, the FN Five-seveN MK3 MRD cannot be stopped. We ran 500 rounds in a mix of three different loads and had zero malfunctions or issues. 

FN Five Seven MRD MK3 pistol in FDE with ammo
The ammo tested with the MRD included Fiocchi-loaded/FN-branded SS197SR 40-grain V-max blue tips, Federal American Eagle 40-grain FMJ target ammo, and 27-grain SS195LF lead-free range loads. (Photo: Chris Eger/Guns.com)


Customer Reviews

Pros & Cons


  • Optics ready for just about every pistol red dot on the market
  • Better ergonomics than past Five-seveN pistols
  • Nice 20+1 magazine capacity
  • Reliable
  • Easy to field strip and maintain.
  • Excellent sights (but could be slightly taller)
  • No factory threaded barrel option


  • Large with a beefy grip which could make it hard for some to use
  • Unusual manual safety orientation
  • Expensive with a $1,500 MSRP
  • Doesn't use legacy Five-seveN mags

Final Thoughts


Now in its 25th year in production, the latest model of the Five-seveN pistol has been updated for the current market. Showing its roots, it nonetheless still has a very 1990s military-issue feel to it. It works without complaint, is accurate enough for use in personal defense, and is easy to maintain and use. Made in Belgium at FN Herstal, the latter European parent company lists the pistol overseas as the "military qualified" Five-seveN Tactical Mk3, pairing it with the select-fire P90 PDW and playing up its recent NATO caliber standardization. We like it as-is, but we'd love it if it were more comparable with the 509/510/545 Tactical series seen here in the states, in other words with an extended threaded barrel, extended (30 round?) mag, and suppressor-height rear sights. 
Further, when compared to its more recently introduced American competitors such as the PSA Rock, the Ruger 57, and S&W's new M&P 5.7-- all of which come in at well under $800-- the $1,500 FN is a bit pricey. Of course, none of those other pistols can vouch for a legacy of being adopted by dozens of overseas Mil/LE services in assorted capacities, which falls well within FN's "World's Most Battle-Proven Firearms" motto. I'd bet the folks looking to buy a new Five-seveN aren't worried too much about the price.


The FN Five-seveN MRD MK3 pistol in FDE. (Photo: Chris Eger/Guns.com)


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