The FN 510 MRD in Flat Dark Earth is a double-action-only 10mm AUTO pistol with a 4.1-inch cold hammer-forged stainless steel barrel with a 1:16 RH twist rate. Capacity is 15+1 rounds. Overall length is 7.7 inches and weight is 31 oz. The frame is FDE textured polymer. The slide has a low-profile optics mounting system accepting multiple optic footprints while maintaining iron sight co-witness. No manual safety. 
 

Key Specifications 

• Brand: FN 
• Model Name: 510 MRD 
• Caliber: 10MM AUTO 
• Action: DAO (Double Action Only) 
• Capacity: 15+1 RD 
• Barrel Length: 4.1" 
• Overall Length: 7.7" 
• Weight: 31 oz. 
• Grip Material: FDE Textured Polymer 
• Sights Type: Driftable Steel Cowitness 
• Safety Features: No manual safety 
• Finish Color: Flat Dark Earth 
   

Detailed Features 

 
Barrel: Cold hammer-forged stainless steel, 1:16 RH twist, trigger pull near 6 lbs. The polished feed ramp improves cycling reliability across different 10mm loads. 
 
Optics Ready Design: Low-profile mounting system fits multiple optic footprints. Co-witness steel iron sights provide a backup aiming option. 
 
Grip and Frame: FDE polymer frame with interchangeable backstraps for hand fit. Ambidextrous slide stop increases usability for left-handed shooters. 
 
Picatinny Rail: Full-length rail on the dust cover accepts tactical lights and lasers. 
 

Usage Scenarios 

• Home Defense: 15+1 capacity in 10mm AUTO is substantial firepower for home protection. 
• Personal Defense Carry: The frame size and weight are toward the larger end for carry but manageable for those willing to commit. 
• Competitive Shooting: The factory optics setup and high capacity work for competition formats that allow them.

The FN 510 MRD in FDE with 15+1 capacity gets strong marks from owners in the 10mm market. Reliability across different ammunition is the most consistently praised feature -- the pistol feeds and ejects cleanly with varying 10mm pressure levels. Build quality follows FN's standard, and the Flat Dark Earth finish looks clean while handling wear reasonably well.

The optics-ready slide and ergonomic grip earn specific praise. Owners note that grip texture is effective without being aggressive, and the handling during extended sessions is comfortable. The 15+1 capacity is frequently cited as a meaningful advantage over competing 10mm platforms.

10mm recoil is noticeable, though most owners find the FN 510's weight (31 oz.) helps manage it compared to lighter 10mm pistols. The recurring criticisms are size -- the 510 is large and heavier than many competitors, which limits carry appeal -- and price, which some find steep. Holster and aftermarket accessory availability is expanding but still narrower than established platforms. Some owners also note limited model-specific accessories.