SIG Sauer M400 Sdi 5.56 NATO 16" 30-Round FDE Rifle

The SIG Sauer M400 SDI 5.56 NATO 16" 30-Round FDE Rifle is a purpose-built modern sporting rifle engineered for law enforcement, military, and civilian tactical applications. Designed by SIG Sauer—a manufacturer with deep roots in both military contracts and professional duty weapons—this platform delivers the reliability and accuracy demanded in high-stakes environments. The 16-inch barrel length provides optimal velocity and handling balance, making it equally effective for close-quarters tactical operations and medium-range precision work.

The M400 SDI features SIG Sauer's proven gas-piston operating system, which reduces carrier tilt, minimizes fouling, and extends component service life compared to direct-impingement designs—a critical advantage in extended-use scenarios. The 5.56 NATO chamber accepts both standard 5.56 NATO and .223 Remington ammunition, offering operational flexibility and cost-effective training opportunities. Weighing 9.94 lbs, the rifle maintains a manageable profile without sacrificing rigidity; the FDE (Flat Dark Earth) Cerakote finish provides enhanced corrosion resistance and a professional aesthetic that blends into diverse operational environments while reducing light reflection.

This rifle benefits law enforcement tactical teams, military units, and serious civilian shooters who require a compact, reliable platform capable of accepting standard AR-15 accessories and optics. The 30-round magazine capacity and 16-inch barrel configuration comply with federal regulations while maintaining practical firepower for home defense, duty use, or competitive shooting. Field-proven by professional end-users, the M400 SDI integrates seamlessly into existing 5.56 NATO logistical chains and works with any Picatinny-compatible mounting system for lights, lasers, and optics.