FN M249S 5.56NATO 18.5 BELT BLK

The FN M249S is the semi-automatic civilian counterpart to FN’s legendary MINIMI / M249 SAW, a platform that has seen decades of service with military forces worldwide. Built by FN to the same rugged standards as its duty-grade counterpart, the M249S delivers unmatched durability, firepower, and presence in a closed-bolt, semi-auto configuration designed for civilian ownership.

Chambered in 5.56×45 NATO, the M249S features FN’s 18.5? cold hammer-forged, chrome-lined barrel, engineered for longevity and consistent performance under sustained fire. The closed-bolt operation enhances accuracy over traditional open-bolt machine gun designs, making this platform as precise as it is formidable.

One of the defining features of the M249S is its dual-feed capability, accepting both standard AR-pattern magazines and disintegrating linked ammunition belts up to 200 rounds. A robust gas system, steel receiver, and quick-change barrel capability reinforce its reputation as a true hard-use firearm. Integrated features such as the folding steel bipod, carry handle, and MIL-STD-1913 top rail ensure rapid deployment and modern optic compatibility.

This is not a novelty firearm — it’s a purpose-built, battle-inspired system for collectors and serious enthusiasts who want one of the most iconic support weapons ever produced, in a legal semi-automatic configuration. Simply put, the FN M249S is as close as it gets to owning a piece of modern military history.

Key Specifications

Caliber: 5.56×45mm NATO

Operation: Closed-bolt, semi-automatic

Barrel Length: 18.5?

Twist Rate: 1:7 RH

Capacity: 200-round belt or 30-round magazine

Weight: 17.2 lbs

Overall Length: 40.75?

Overall Height: 9.5?

Trigger Pull: 8 – 15.5 lbs

Primary Features

Semi-auto civilian replica of the government-issue FN M249 SAW

Robust gas-operated system designed for sustained use

Dual-feed system: magazine-fed or belt-fed operation

Closed-bolt design for improved accuracy

Receiver & Controls

Formed steel receiver with claw extractor design

Fixed, pivoting ejector with side case ejection

Integrated MIL-STD-1913 top rail for optics

Folding steel bipod and carry handle

Flip-up feed tray cover and feed mechanism

Cross-bolt safety and curved trigger for improved control

Non-reciprocating charging handle

Redesigned semi-auto trigger mechanism

Barrel System

Quick-change barrel capability

Cold hammer-forged steel construction

Chrome-lined bore and chamber

Removable heat shield

Stock & Recoil Management

Ergonomic polymer buttstock

Hydraulic recoil buffer system

Non-slip buttplate for added stability

Feed System

Standard disintegrating link belt-fed capability

Under-mounted polymer ammunition container helps keep ammunition cleaner, reducing wear and improving reliability