FN 510 MRD 10mm 4.1″ FDE Optic-Ready 15+1
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About this product
What is the FN 510 MRD 10mm 4.1″ FDE Optic-Ready 15+1? It is a full-size, striker-fired pistol chambered in 10mm Auto, built on a polymer frame with an optics-ready slide and designed for high-capacity defensive or backcountry use. This platform bridges the gap between duty-sized handguns and more specialized hunting sidearms, offering modern features in a potent caliber that demands respect and proper handling.
What is the FN 510 MRD used for?
It serves as a high-capacity defensive or backcountry firearm, delivering 15+1 rounds of 10mm Auto in a duty-sized package ideal for bear defense or law enforcement applications. The 4.1-inch cold hammer-forged barrel provides manageable recoil and improved velocity over compact 10mm options, while the optic-ready slide allows for rapid threat acquisition in low-light conditions.
How does the FN 510 MRD compare to the Glock 20?
The FN 510 MRD offers superior out-of-the-box optics readiness and ergonomics compared to the Glock 20 Gen4, which requires aftermarket milling for most red dots. While both share similar 15+1 capacity, the FN's 4.1-inch barrel is 0.2 inches shorter than the Glock's 4.6-inch barrel, making it slightly more compact for holstering, though the Glock maintains a broader aftermarket support network.
What does it weigh and what are the dimensions?
Unloaded weight is 31 ounces (879 grams) with overall dimensions of 7.8 inches long, 5.6 inches tall, and 1.45 inches wide. This places it squarely in full-size pistol territory, comparable to duty 9mm platforms but with the heft needed to manage 10mm recoil—noticeably heavier than compact options like the the Stevens 334 Rifle but balanced for controlled shooting.
Who is this NOT for?
This is not for new shooters or those sensitive to recoil, as 10mm Auto generates approximately 30% more felt recoil than .40 S&W in similar platforms. If you prioritize concealed carry or lightweight packing, consider a compact 9mm or the Stevens 555 Sporting Compact shotgun instead—this FN demands practice and strength to run effectively.
What's in the box?
You receive two 15-round magazines, four MRD mounting plates (covering popular footprints like RMR and DeltaPoint), interchangeable backstraps, and a premium zippered case. The package is complete for optics mounting out of the box, unlike many competitors that force you to buy plates separately—a $60-100 value saved immediately.
Is the FN 510 MRD worth it at $819?
At $819, it justifies its price with factory optics readiness, cold hammer-forged barrel, and FN's military-grade QC, avoiding the $200-$300 aftermarket milling cost of comparable pistols. For shooters needing a rugged 10mm platform ready for red dots, it's a smart investment—but if you won't use an optic, a basic Glock 20 saves $200 for ammo.
Specs at a glance
Pros & cons
What works
- Optic-ready out of the box—includes 4 mounting plates ($100+ value saved)
- 15+1 capacity—holds 3 more rounds than Glock 20 in same size frame
- Cold hammer-forged 4.1" barrel—extends barrel life to 20,000+ rounds
Trade-offs
- 31 oz unloaded—7 oz heavier than polymer compact 9mms, fatiguing for all-day carry
- 10mm ammo costs $0.50/round vs $0.25 for 9mm—doubles training expense
- No threaded barrel option—requires aftermarket conversion for suppressors ($200+)
Key attributes
| upc | 845737015640 |
| manufacturer | FN America / FN Herstal |
| manufacturer part number | 66-101380 |
| action | Semi-Auto |
| atf type | Pistol |
| barrel finish | Black |
| barrel length | 4.10" |
| caliber/gauge | 10mm |
| capacity | 15 |
| color | Flat Dark Earth |
| length | 11.9500 |
| model | FN 510 MRD |
| number of magazines | 2 |
| package height | 3.3 |
| package width | 11.1 |
| product type | Striker Fired |
| safety | No |
| shipping weight | 4.1 |
| sights | Optic Height Sights |
| sights type | Driftable Steel Co-Witness |
| slide description | Optic Cut/Serrated |
| state restriction (ca) | NO DIRECT SHIP TO CALIFORNIA |
| state restriction (ri) | NO DIRECT SHIP TO RHODE ISLAND |
| state restriction (wa) | NO DIRECT SHIP TO WASHINGTON |
Frequently asked questions
- Is it compatible with Trijicon RMR optics?
- Yes, it includes Plate #1 for Trijicon RMR/SRO footprints—no adapter needed. Mounting requires four 4-40 screws provided, and zeroing takes about 12 rounds at 25 yards. Ensure you use thread locker to prevent shift under recoil.
- Does it fit standard Safariland holsters?
- It fits Safariland 6000-series holsters for full-size .40/.45 pistols, but verify model-specific compatibility. Holster draw clearance is 1.45 inches wide, so check for optic interference—some ALS models require modification for taller red dots.
- How long does shipping take?
- FFL shipments process in 2-3 business days after payment clearance, with transit via UPS or FedEx taking 3-5 days. Delays occur if your FFL hasn't faxed paperwork—always confirm their license is on file with Ironclad Armory.
- Can I return it if it doesn't fit my hand?
- No, firearms are non-returnable per ATF regulations once transferred. Use the interchangeable backstraps to adjust grip circumference from 1.3 to 1.5 inches—if that doesn't work, resell through an FFL. Measure your hand first; this is a large-frame pistol.