The Colt M4 OEM1 is a semi-automatic 5.56 NATO carbine in blue and black, built on the Colt M4 platform. It has a 16.1-inch chrome-lined barrel with a 1:7 twist, a receiver with a Picatinny rail, an A2 front sight base and a carbine-length gas system. The OEM1 is supplied without a handguard, buttstock, trigger guard, magazine or rear sight, so it is a starting point for a custom build. The listed overall length is 32 inches.

This carbine suits builders and dealers who want a Colt M4 foundation for a custom 5.56 NATO rifle. Owners add their own handguard, stock, trigger guard and sights to match the use, whether that is range work or a defensive setup. The rifle accepts standard AR-15 magazines, which are sold separately because none are included.

Key features

• 16.1-inch chrome-lined barrel with 1:7 twist
• Picatinny-railed receiver with Picatinny rail
• A2 front sight base and carbine-length gas system
• Accepts standard AR-15 magazines, none included
• No handguard, stock, trigger guard or rear sight

This carbine ships to the licensed FFL dealer you name, where you complete Form 4473 and pass a NICS check before you take it home.