FN Five-seveN MK3 MRD 5.7x28mm vs Ruger-57 5.7x28mm

Both pistols hold 20+1 rounds of 5.7x28mm and run the same 4.8-4.94" barrel length, but they target different buyers. The FN is 0.15" narrower (1.20" vs 1.35") and runs a single-action trigger that reviewer tests put in the 4.4-7.87 lb range; the Ruger publishes a 5-6 lb factory pull and adds 0.45" to overall length at 8.65". The bigger split is build and price: FN's Belgian-made polymer-jacketed steel slide with a 7" sight radius sits against Ruger's American glass-filled nylon frame and fiber-optic front, and street prices typically separate the two by roughly $800.

Pick the FN Five-seveN MK3 MRD if:

• You want the original NATO and law-enforcement-adopted platform with documented service history and the largest holster and accessory ecosystem in the 5.7x28mm category
• You prefer the 0.15" narrower 1.20" slide profile and the polymer-jacketed steel construction over the Ruger's glass-filled nylon frame for long-term durability
• You want the factory adjustable rear sight paired with a 7" sight radius — the Ruger does not publish a sight radius spec and ships with a fixed rear setup

Pick the Ruger-57 if:

• You want 5.7x28mm at roughly half the street price of the FN — the cost gap has not meaningfully closed since the Ruger's 2020 launch
• You prefer the Ruger's published 5-6 lb bladed-safety trigger as a more consistent factory pull — reviewer measurements of the FN's single-action vary widely from the low 4s to nearly 8 lbs depending on the test
• You want a factory fiber-optic front sight for faster target acquisition in varied lighting without aftermarket sight work

Both run optic-ready slides, ambidextrous safeties, 1:9" twist barrels, and ship with two magazines. The decision comes down to whether the FN's Belgian manufacturing and adoption pedigree justify roughly twice the street price over a Ruger that hits the same capacity with a more predictable factory trigger.