Review: FN America 509C MRD Pistol

posted on April 28, 2020

At the FN America new-product launch, the assembled media types were given a quick presentation even before the firearm was unveiled. FN, a company that has long heavily emphasized military and law enforcement sales, claimed to be interested in paying greater attention to the needs of the gun-owning private citizen in America.

The pistol it then unveiled would seem to support this claim. Rather than being another duty-size service handgun, what was presented was a chopped-down version of the popular FN 509 handgun, dubbed the 509C, for Compact.

While it’s dubbed a Compact, FN has followed the pattern of the first-generation Smith & Wesson M&P Compact and built a handgun that splits the size difference between the subcompact G26 and “compact” G19 from Glock.

The 509C sports a 3.7-inch barrel, giving it a bit over a quarter inch more barrel length and sight radius than the Gen5 Glock G26, which isn’t a huge difference. But, that extra length means the 509C’s polymer dustcover features a MIL-STD-1913-compatible accessory rail with three mounting slots, versus zero mounting slots on the Glock G26. 

Low-Profile Optics Mounting System, pistol grip, sights
Thanks to FN’s Low-Profile Optics Mounting System, the 509 Compact can accept multiple MRDS models • Numerous types of texturing adorn the pistol’s grip to provide ample purchase • The sights are tall enough to co-witness with a red-dot sight while possessing sufficient clearance for use with a suppressor

The 509C’s rail is actually long enough to accommodate a full-size mounted weaponlight like the SureFire X300U, although it will protrude rather a lot off the front end of the pistol. A compact light like Streamlight’s TLR-7, on the other hand, fits so tidily it looks like it should be offered as a factory option.

The test pistol was technically a 509C MRD, which has FN’s proprietary two-piece mounting plate setup for slide-mounted miniature red-dot sights. While the most rock-solid manner to attach an MRDS to a slide is to have an experienced shop machine the slide to fit your specific sight, FN’s adapter-plate setup is probably the best of the interchangeable-adapter ones on the market right now. The thumbnail version of how it works is that it sandwiches a donut cross-sectioned rubber O-ring between the lower plate and the slide, which provides tension to keep the screws from vibrating loose.

The test gun was the same Flat Dark Earth color scheme as the 509 Tactical which, while less than necessary on a CCW pistol, is still kinda cool-looking and a break from yet another flat-black, plastic, striker-fired gat.

trigger guard, 15-round magazine, accessory rail
There is enough room inside the trigger guard for a gloved finger • Twelve- and 15-round magazines ship with the gun • The dustcover boasts an accessory rail.

The frame offers the same combination of textures as its full-size sibling, which range from a slightly rough texturing high on the grip where your thumbs go, through small sharp pyramids on the sides of the grip, to large aggressive pseudo-checkering on both the front and backstrap(s). While this is definitely grip texturing that will ensure the pistol stays anchored in your mitts, at high-round counts, it could have you reaching for the moleskin. One area of note was on the adapter collar of the longer magazine (the test gun shipped with 12- and 15-round units). While the longer magazine gives an even firmer rest for your pinkie finger than the sculpted pinkie rest on the short one, the magazine moves enough under recoil that it eventually left a raw spot on my little finger after a particularly long day at the range. (And it’s in a spot not normally associated with shooting, so it wasn’t until the next day’s range trip that I figured out where the mystery boo-boo had come from.)

All the control elements of the 509 series are retained on the C-model, including ambidextrous slide and magazine releases, and the MRD version comes with plain-black suppressor-height sights. The trigger is of the two-piece hinged variety, à la the M&P, and on the test gun it broke consistently at 6 pounds. While the break was clean, takeup remained a bit gritty even nearly 1,000 rounds into the testing. It was a usable trigger, but not one about which you would write poems.

FN 509C MRD shooting results

At FN’s launch event, we ran the guns through an abbreviated 1-day version of trainer Aaron Cowan’s red-dot and low-light curricula. I used a TLR-7 light and a Trijicon SRO optic, running the gun from concealment in a strong-side Kydex IWB holster. By the time we knocked off after 9 pm, the guns had chewed through probably close to 600 rounds of ammunition with no hiccups, and my test sample has continued to function without issue for several hundred rounds more. This one may be a keeper.

FN 509C MRD side view
FN  509C MRD specs


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