The Colt M4 OEM1 Carbine is a semi-automatic 5.56 NATO rifle designed for customization on the proven Colt M4 platform. This factory configuration includes a 16.1-inch chrome-lined barrel with a 1:7 twist rate, an A2 front sight base, a flat-top receiver with Picatinny rail, a carbine-length gas system, and a pistol grip. The OEM1 intentionally omits the handguard, buttstock, trigger guard, magazine, and rear sight, giving builders and dealers a flexible starting point for a personalized setup. The rifle uses standard AR-15 magazines and accepts a wide range of aftermarket components.

Key features

• Colt M4-based semi-automatic rifle chambered in 5.56 NATO
• 16.1-inch chrome-lined barrel with a 1:7 twist rate
• A2 front sight base with a flat-top Picatinny receiver rail
• OEM configuration ready for aftermarket handguard and buttstock installation
• Carbine-length direct-impingement gas system
• Accepts standard AR-15 magazines with a 30-round capacity specification

The Colt M4 OEM1 Carbine provides a dependable factory foundation for a customized 5.56 NATO rifle build.