Spikes Tactical STU5025M4S Complete AR-15 Upper 5.56 NATO 16″

Description

The Spikes Tactical STU5025M4S is a complete AR-15/M16 upper receiver assembly built to Mil-Spec standards for service-grade reliability and consistent performance. It is chambered for .223 Rem/5.56 NATO and features a 16″ chrome-moly barrel with a 1:7 rate of twist and M4 barrel profile. The assembly includes an A2 front sight base, M4 double heat shield handguards, and a Spike’s Tactical Mil-Spec M16 bolt carrier group. This configuration is suitable for general-purpose AR-15 builds, range use, and platform upgrades where a carbine-length gas system and familiar M4 ergonomics are desired.

Key Specifications

• The cartridge is .223 Rem/5.56 NATO.
• The barrel measures 16 inches and uses an M4 profile.
• The barrel material is Chrome Moly.
• The barrel finish is Black Phosphate.
• The twist rate is 1:7.
• The gas system is a carbine-length setup with a .750″ diameter gas seat.
• The handguards are M4 Double Heat Shield in a black finish.
• The receiver is 7075-T6 aluminum with a black finish.
• The front sight is an A2 F-marked front sight base.
• The upper ships as a complete assembly including a Spike’s Tactical Mil-Spec M16 bolt carrier group and A2 flash hider.

This complete Spikes Tactical upper brings Mil-Spec components and proven AR-15 geometry together in a familiar M4 configuration. Its 16″ 1:7 barrel and carbine gas system offer a versatile balance of controllability and consistency for general shooting applications, while the included heat-shield handguard and A2 sight preserve classic ergonomics. For builders and shooters who want a straightforward, serviceable upper built to spec, the STU5025M4S is a dependable option.