TFB Review: Red Dot Ready FN America Pistols

Over the last few years, red dots on pistols have moved from an anomaly found on some competition pistols into the mainstream. Many of us carry them every day on our concealed carry pistols and appreciate the improved sight picture and precision they provide. FN manufactures a broad range of handguns compatible with red dot sights and they sent me a range of them to try out.

FN @ TFB:

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• TFB Review: FN 502 MRD And 502T

Disclosures: FN let me borrow these pistols for this sponsored article. I paid for the ammunition.

FNX-45 Tactical

Our tour begins with the pistol that started the slide-mounted optic party. The FNX-45 Tactical is a double/single-action pistol with an external hammer. The safety lever also acts as a decocker for carrying with a loaded chamber and the hammer down. Other features include a 15-round magazine, interchangeable backstraps, and a threaded barrel.

FN pioneered the idea of slide-mounted micro pistol dots, though bullseye and action pistol shooters had been using various types of red dots on slide or bridge mounts for some time. To split some hairs, the FNX-45 Tactical was not the first model with this kind of mounting system. That would be the different-but-almost-identical FNP-45 Tactical, which was replaced by the FNX-45 Tactical.

FN includes two red dot mounting plates with the FNX, one for the RMR footprint and one for the old Docter cut. Almost nothing uses the Docter footprint these days, but the RMR still remains one of the most popular patterns. I mounted a Holosun EPS (using Holosun’s included adapter that converts it to an RMR footprint) with little drama. Thanks to the plate-on-a-plate setup, this dot sits a little high to co-witness with the iron sights, but they line up correctly with a standard RMR or 507.

The FNX-45 is a natural suppressor host, and between the bulk of a silencer and the overall size of a gun that holds 15 rounds of .45 ACP, adding on a red dot doesn’t make the gun much bigger. It also fits with the general “vibe” of a pistol like this, which was developed for the Joint Combat Pistol program. The military never selected a winner for that program, but a red dot sight on a more offensively-oriented pistol (yes that’s a reference to the earlier Offensive Handgun Weapon System trials that share a lot of common features with JCP program goals) is a natural fit.

FN 509 LS Edge

Fast forward to the last few years and we reach the FN 509 series. The 509 is striker-fired and descends from the FNP and FNS series of handguns. The LS Edge model in particular is competition-oriented with an extended barrel and flat-face trigger.

This newer design also incorporates newer red dot mounting options. One thing that FN nails with this pistol is the suite of red dot mounting equipment and information. Rather than digging through a packet of parts and using trial and error to find the right plates and screws. Instead, each plate and the appropriate screws are packed in neat little columns and rows in a plastic sheet.

The instructions are similarly well thought out. With both pictures and text it clearly lays out which plates and screws work with each style of red dot. The instruction sheet is also drawn to scale and if the screws were to get confused, setting them on the instruction sheet with the corresponding image can get them sorted out again. The instructions state that an adapter plate for the Aimpoint Acro footprint is not included, but one was in the box. I do not know whether that is standard practice or whether that was included for a media sample gun, but I planned to use an Acro footprint dot so I was glad to see it in the package.

The Lead & Steel Pandora PB-3 is a fully enclosed sight that uses the Aimpoint Acro footprint. That style of optic tends to be larger and heavier than a smaller sight like an RMR. Despite the extra bulk, the 509 LS Edge ran well with all ammunition types that I tried. A larger dot like this enclosed model, or something like a 507 Competition would be natural on a gun like this.

Reflex MRD

The Reflex is a smaller pistol than the two we discussed above, designed for concealed carry. These micro 9mm pistols take a standard striker-fired handgun and shrink it down while still keeping a lot of the capacity from the bigger guns. This style of handgun has dominated the concealed carry scene for the last seven or eight years.

These micro 9mm pistols usually have thinner slides that are not wide enough for earlier optic footprints like the RMR. The MRD model incorporates a dedicated optics cut for RMSc footprints. That mounting pattern (including the almost-the-same-but-not-quite Holosun K pattern) is the unquestioned leader for smaller handguns, particularly those with narrower slides. Many sights use this footprint, and I selected a ZeroTech Thrive HD that I had on hand to use on this gun. Mounting the optic is very easy; because this is a direct-mount system, the red dot sits on the two threaded posts. FN supplies appropriate screws and I torqued those down using a Wheeler FAT Wrench. Unlike the 509 LS Edge, which has options for all sorts of red dots, the Reflex MRD does not need all of the complication. Just pick an RMSc dot and screw it onto the slide directly with the included screws.

A smaller, lighter red dot is the move on a gun like this. Large windows or the bulkier enclosed dots can be obstructive on a concealment gun the size of the Reflex MRD. But even with a smaller optic on a smaller gun, adding an optic makes a big difference. It is much easier to hit small targets at extended ranges than using iron sights. The Reflex fills the same size niche as snubnose revolvers but is far easier to shoot well.