CMMG Barrel Sub-Assm 16.1inch MT 4140CM SBN 5.56mm

Perfect for building your custom AR15 upper group. Comes with properly installed M4 barrel extension. All barrel sub-assemblies are properly headspaced.

• 16.1?
• Medium Taper Profile
• 4140 Chrome Moly
• Salt Bath Nitride Finish inside and out
• 1:7 Twist
• 5.56×45 NATO Chamber
• Threaded 1/2-28
• Midlength gas port
• .750? Gas Journal