FN 545 MRD .45 ACP 4.1-inch Black
- Firearms ship to the FFL dealer you choose, in any state
- Free shipping on orders over $99 · ships in 1–2 business days
- 30-day returns on unused parts and accessories
About this product
The FN 545 MRD .45 ACP 4.1-inch Black is a full-size, optics-ready service pistol built for shooters who want proven ergonomics and modern features. It combines a cold hammer-forged barrel with a polymer frame and a slide cut that accepts multiple MRD footprints, making it ready for red dot sights right out of the box.
| Manufacturer | FN America |
|---|---|
| Model | 545 MRD |
| Material | Cold hammer-forged steel barrel, polymer frame with steel inserts (per manufacturer specs) |
| Compatibility | Accepts multiple MRD footprints (RMR, RMSc, Docter, and more) with included plates |
| Finish | Black nitride slide, black polymer frame |
| Weight | 28.2 oz (empty, with standard magazine) |
| Condition | New |
Key Features
- Optics-Ready Slide: The slide is pre-cut to accept multiple MRD footprints, so you can mount your favorite red dot without sending the slide out for machining. Why it matters: Saves you time and money while keeping the pistol ready for fast target acquisition.
- Cold Hammer-Forged Barrel: The 4.1-inch barrel is cold hammer-forged and crowned for consistent accuracy and long service life. Why it matters: You get a barrel that holds up to thousands of rounds without losing precision, even with hot .45 ACP loads.
- Ambidextrous Controls: Slide stop and magazine release are fully ambidextrous, making the pistol natural for both right- and left-handed shooters. Why it matters: No fumbling to drop a mag or lock the slide back under stress—it works for everyone.
- Premium Zippered Case: Comes in a padded, zippered case with two magazines, a cable lock, and three MRD mounting plates. Why it matters: You don’t have to buy extra gear to get started; everything you need is in the box.
Who It’s For
This pistol is for the shooter who wants a full-size .45 ACP that’s modern and ready for optics. It’s ideal for home defense, range shooting, or duty use. New gun owners will appreciate the easy controls and included case; experienced shooters will value the cold hammer-forged barrel and MRD compatibility.
Pros & Cons
- Pros: Optics-ready out of the box, ambidextrous controls, cold hammer-forged barrel, reliable feeding with various .45 ACP ammo, great factory trigger.
- Cons: The grip texture can be aggressive for some shooters—you might want to wear a glove or add grip tape for extended range sessions.
Comparison
| Feature | FN 545 MRD | Glock 21 Gen5 | Sig Sauer P320 Full Size .45 |
|---|---|---|---|
| Caliber | .45 ACP | .45 ACP | .45 ACP |
| Barrel Length | 4.1 in | 4.6 in | 4.7 in |
| Weight (empty) | 28.2 oz | 30.0 oz | 30.5 oz |
| Optics Ready | Yes (multiple MRD footprints) | No (requires aftermarket cut) | Yes (X-Series slide) |
| Ambidextrous Controls | Yes (slide stop & mag release) | Yes (slide stop only) | Yes (reversible mag release) |
| Street Price | $819 | $599 | $749 |
FAQ
Is the FN 545 MRD compatible with red dot sights?
Yes, the slide is cut to accept multiple MRD footprints including Trijicon RMR, Shield RMSc, Docter, and more. Three mounting plates are included in the box.
Does the FN 545 MRD come with extra magazines?
It comes with two 15-round magazines, a cable lock, and the padded zippered case.
Is the FN 545 MRD good for left-handed shooters?
Yes, the slide stop and magazine release are fully ambidextrous, so left-handed shooters can operate it without any modifications.
What is the barrel twist rate on the FN 545 MRD?
Per FN America specs, the barrel has a 1:16-inch twist rate, optimized for standard .45 ACP ammunition.
Can I use +P ammunition in the FN 545 MRD?
Yes, the pistol is rated for +P .45 ACP loads, though extended use may accelerate wear on the recoil spring.
Over 2 million shooters in the U.S. own a .45 ACP handgun for home defense—and the FN 545 MRD gives you modern optics capability with proven reliability.
- ✓ Nationwide delivery (all 50 states)
- ✓ Ships 1-2 business days
- ✓ 30-day returns
- ✓ Secure checkout
Browse more in our Semi Auto Handguns or FN Handguns categories. Need a holster? Check out our Holsters.
Last updated: April 2026