HM Defense HM15FMB556L Defender M5L 5.56 NATO 16" Barrel 30+1

The HM Defense HM15FMB556L Defender M5L delivers reliable semi-automatic performance in the proven 5.56x45mm NATO chambering. This carbine-length platform combines mil-spec construction with enhanced ergonomics for versatile applications from competition to duty use. The 16-inch barrel length provides optimal velocity while maintaining maneuverability in confined spaces.

What Makes This Different

Built on HM Defense's proven M5L platform, this rifle features a hard coat anodized finish that exceeds standard Type III specifications for corrosion resistance. The enhanced polymer grip provides improved texture and ergonomics compared to standard A2-style grips. The mil-spec buffer tube and stock ensure compatibility with aftermarket components while maintaining reliable function.

Key Features

• 5.56x45mm NATO chamber accepts both 5.56 NATO and .223 Remington ammunition
• 16-inch barrel with 1:7 twist rate optimized for 55-77 grain projectiles
• 30-round capacity magazine with anti-tilt follower design
• Black hard coat anodized finish rated for 2,000+ hour salt spray resistance
• Mil-spec trigger group with 6-8 pound pull weight
• Enhanced polymer pistol grip with finger grooves and palm swells
• Standard Picatinny rail system for optics and accessories

Field testing demonstrates consistent 2-3 MOA accuracy with quality ammunition across various bullet weights. The carbine-length gas system provides reliable cycling with both brass and steel-cased ammunition while reducing bolt carrier velocity for extended component life. The platform functions reliably in temperature ranges from -20°F to 140°F with minimal maintenance requirements.

Technical Specs

• Caliber: 5.56x45mm NATO/.223 Remington
• Barrel Length: 16 inches
• Overall Length: 32.75 inches (stock collapsed), 36.25 inches (extended)
• Weight: 6.8 pounds (unloaded)
• Magazine Capacity: 30+1 rounds
• Twist Rate: 1:7 inches
• Gas System: Carbine length
• Finish: Black hard coat anodized Type III
• Stock: 6-position collapsible mil-spec
• Barrel Material: Chrome moly vanadium steel
• Thread Pitch: 1/2x28 TPI

The HM15FMB556L represents solid engineering focused on function over flash. Current production models ship with upgraded components that address common AR-15 platform concerns. Availability remains strong despite increased demand in the tactical rifle market.