The FN 545 MRD is a single-action-only .45 ACP semi-automatic pistol with a 4.1-inch hammer-forged barrel, 15+1 capacity, and a matte black finish. The optic-ready slide uses a direct-mount cut for micro red dots and ships with driftable steel co-witness sights. 
 

Key Specifications 

• Brand: FN 
• Model: 545 MRD 
• Caliber: .45 ACP 
• Action: Single Action Only (SAO) 
• Capacity: 15+1 rounds 
• Barrel Length: 4.1 inches 
• Overall Length: 7.70 inches 
• Weight: 30 oz (1.875 lbs) 
• Sights: Fixed Configuration Driftable Steel Co-Witness 
• Grip Material: Black Textured Polymer 
• Finish: Matte Black 
• Safety Feature: No Manual Safety 
   

Detailed Features 

The hammer-forged barrel has a target crown for consistent bullet exit. The optic cut on the slide accepts micro red dots directly, co-witnessing with the driftable steel sights. The textured polymer grip provides traction in most shooting conditions. The ambidextrous configuration works for left- and right-handed shooters. No manual safety — the SAO design relies on trigger geometry. At 15+1 rounds the 545 MRD offers substantially more capacity than legacy single-stack .45 ACP designs. 
 

Usage 

The 545 MRD in matte black suits duty, home defense, and competition use for shooters who prefer .45 ACP. The optic-ready slide with co-witness backup sights makes it practical for red dot use. At 30 oz it manages .45 ACP recoil without requiring a heavy steel frame. The 15+1 capacity closes the gap between this and modern 9mm competitors.

The FN 545 MRD in matte black draws consistent praise for quality and reliability. FN's build reputation is well-established, and the 545 delivers on it in owner reports. Cycling is reliable, accuracy is solid, and the pistol handles .45 ACP recoil well at 30 oz.

The optic-ready slide with co-witness height is the most commonly praised feature. It's a clean implementation — the sights remain usable if the optic is removed, and the direct-mount cut works with standard micro red dot footprints.

The 15+1 capacity comes up favorably in comparisons to 1911 single-stack designs. Owners appreciate having more rounds available in a .45 ACP platform without moving to 9mm.

Ergonomics are well-received. The grip texture is aggressive enough for control without being uncomfortable. Ambidextrous controls work for both shooting orientations, and the overall layout is intuitive.

No manual safety is noted as a design characteristic worth understanding before purchase. Shooters coming from manual-safety platforms adapt with training; those who specifically want a safety lever should look elsewhere. Cost comes up in discussions — the FN 545 carries a price premium over some competitors that buyers need to weigh against the build quality and features.