The CMMG 8.6 Blackout barrel sub-assembly (CMMG part number 33D430C) is a complete, ready-to-install barrel measuring 12.5 inches, finished in a sleek, corrosion-resistant black nitride. Machined from 4140CM chromoly steel with a fast 1:3 twist rate to stabilize the 8.6 Blackout cartridge’s heavy bullets, it is compatible with CMMG Mk3 and DPMS Gen 1 High-Pattern LR-308 upper receivers and accepts a standard 0.750-inch diameter gas block. It is a solid way to kick off an 8.6 Blackout rifle build.

Key Specifications

• Chambered in 8.6 Blackout.
• Measures 12.5 inches in length.
• Rifled with a fast 1:3 twist rate.
• Finished in black nitride for corrosion resistance.
• Machined from 4140CM chromoly steel.
• Compatible with CMMG Mk3 upper receivers.
• Compatible with DPMS Gen 1 High-Pattern LR-308 upper receivers.
• Accepts a 0.750-inch diameter gas block.
• Sold as a complete barrel sub-assembly, ready to install.

Frequently Asked Questions

What upper receivers is this barrel compatible with? CMMG Mk3 and DPMS Gen 1 High-Pattern LR-308 upper receivers.

What twist rate does it use? A fast 1:3 twist, matched to 8.6 Blackout’s heavy bullets.

What gas block size does it accept? 0.750-inch diameter.

Buy the CMMG 8.6 Blackout Barrel Sub-Assembly

Kick off your 8.6 Blackout build with a complete, ready-to-install barrel. Order this CMMG barrel from our AR barrels lineup, shipped fast from our Lubbock, Texas gun shop.