CMMG MK4 Tungsten Upper Receiver Assembly 223 Rem/5.56 NATO 14.5"

The CMMG MK4 Tungsten is a complete AR-15 upper receiver assembly chambered in 223 Rem/5.56 NATO, built around a 14.5" steel barrel. The barrel features a 1:7" twist rate optimized for heavier projectiles and utilizes a carbine-length gas system for reliable cycling. This upper assembly is designed for AR-15 platforms and provides a solid foundation for tactical and sporting applications. The MK4 series represents CMMG's commitment to quality manufacturing and precision engineering.