| Caliber | 5.56x45mm |
| Barrel Length | 12.5 |
| Barrel Twist | 1:7 |
| Barrel Contour | Multi Role |
| Barrel Material | 4140CM |
| Barrel Twist | 1:7 |
| Muzzle Thread | 1/2 X 28 |
| Gas Port Location | Carbine |
| Gas Block | 0.750" |
AR Parts Notice - State/local restrictions may apply in CT, DC, IL, MA, NJ, NY, or WA. Customers must review our Shipping Policy prior to ordering.
Barrel Sub-Assm, 12.5" MR 4140CM SBN, 5.56mm
Perfect for building your custom AR15 upper group. Comes with a properly installed M4 barrel extension. All barrel sub-assemblies are properly headspaced.
**All NFA rules apply** See linked CMMG Resource article for more information.
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