Buy FN 509® Midsize MRD.

Looking for a premium vibe? Look no further.

Your EDC just got better with the all-new FN 509® Midsize MRD.

This evolution of the FN 509 Midsize, now featuring the FN Low Profile Optics Mounting System, gives you the option of direct mounting more than 10 different miniature red dot optics to your concealed carry pistol. The FN 509 Midsize MRD features a four-inch barrel and slide with optics mounting package, a midsized frame, standard 15-round capacity and is compatible with larger capacity FN 509 magazines with use of a sleeve. The improved controls aid in manipulation, the new improved texturing on the two included backstraps…

Experience unmatched reliability and performance with the legendary FN 509® Midsize MRD. Designed for professional operators and tactical enthusiasts alike, this firearm sets the standard for modern shooting. Built on battle-proven engineering, our featured FN SCAR selection utilizes cold hammer-forged barrels and precision-machined receivers to deliver sub-MOA accuracy. Every shot offers a crisp trigger break and clean cycling. Upgrade your loadout by shopping through our official shop page, or browse the FN 509® Series section to check current model availability.

The engineering behind FN 509® Midsize MRD focuses on ergonomics and recoil mitigation. Features like ambidextrous safety selectors, magazine releases, and charging handles ensure fast manipulation in high-stress situations. The MIL-STD 1913 Picatinny rails provide ample space for tactical lights and optics, making it adaptable to any mission profile. Learn more about our firearm designs on our site.

Key Features and Benefits

Cold Hammer-Forged Barrel: Chrome-lined bore ensures long service life and corrosion resistance.
Optics-Ready Receiver: Features cutouts for mounting red dot sights and iron sights easily.
Ambidextrous Controls: Designed for left-handed and right-handed shooters without modifications.

Firearm Safety & Training Guidelines

Always treat the firearm as if it is loaded. Practice safe muzzle discipline and keep your finger off the trigger until you are ready to fire. Clean the barrel and action after every range session to maintain cycling.

User Level	Recommended Drills	Rest Period
Novice Shooter	Basic grip and sight alignment.	Every 50 rounds.
Advanced Operator	Transition and reloading drills.	Every 150 rounds.

Technical Specifications

Parameter	Specification	Details
Caliber / Gauge	Various / Semi-Automatic	High-impact tactical build.
Barrel Length	MIL-SPEC Spec	Cold hammer-forged steel.

Our rifles and pistols undergo rigorous test firing at the factory to verify function, extractor strength, and sight alignment before packaging. This guarantees that your firearm performs straight out of the box.

We source our raw polymer and high-strength steel from certified aerospace suppliers who prioritize structural purity. This ensures that every receiver resists cracking under heavy firing schedules and thermal load.

The gas system in our rifles utilizes a short-stroke piston design that keeps hot gases and carbon residue away from the bolt carrier. This leads to a cooler running action and less cleaning downtime.

Our quality control managers check barrel concentricity, chamber dimensions, and head spacing on every single build to maintain tight accuracy tolerances. We believe in providing operators with complete battlefield reliability.

The receiver features a durable hard-coat anodized or flat dark earth finish that resists moisture, sweat, and salt spray. It is built to survive in freezing rain, muddy trenches, and desert heat.

With our modular buttstock system, you can adjust the length of pull and cheek riser height in seconds. This allows you to fit the rifle perfectly to your body armor and optics configuration.

Our trigger assemblies are tuned to provide a crisp, clean break with a positive reset. This helps you maintain stability during rapid follow-up shots and improves overall target groups at long distance ranges.

Important Warnings and Firearm Disclaimer

This firearm is strictly for law-abiding adult citizens. Always check local and federal regulations before purchase and verify NFA compliance where applicable. Store locked and separate from ammunition. For official owner manuals, safety data, and NFA registrations, visit our official page for more information.