CMMG 16.1 in .300 AAC Blackout Barrel Sub-Assembly

This CMMG barrel sub-assembly is built for assembling a custom AR-15 upper and ships with a properly installed M4 barrel extension and factory head spacing. The barrel is constructed from 4140 chromoly steel and finished with a nitride treatment for enhanced surface hardness and corrosion resistance. It is chambered for .300 AAC Blackout and configured in a carbine-length gas system with a multi-role profile to suit a range of AR-15 applications. The muzzle is threaded 5/8-24 to accept common muzzle devices.

Key Specifications

• The cartridge is .300 AAC Blackout.
• The barrel length is 16.1 inches.
• The barrel material is 4140 chromoly steel.
• The external finish is Nitride.
• The twist rate is 1:7.
• The gas system length is Carbine.
• The muzzle threads are 5/8-24.
• The barrel profile is a Multi Role Profile with a Medium contour.
• The barrel weight is approximately 2.205 lbs.
• Designed for the AR-15 platform.

This barrel sub-assembly delivers a durable, serviceable foundation for a capable .300 AAC Blackout AR-15 upper. Its combination of 4140 chromoly construction, nitride surface treatment, carbine gas system and 1:7 twist makes it suitable for a variety of utility and precision-minded builds where reliability and material quality matter.