300BLK earned its reputation in platforms just like this — short, compact, and purpose-built.
The ZEROED BANSHEE Mk4 Upper Group gives you the Direct Impingement reliability of the Mk4 platform with a ZEROED Faux Suppressor that tucks inside the oversized Dad Bod™ handguard (M-LOK compatible).
The result is a suppressor-profile build that looks the part without the NFA tax stamp or suppressor regulations.
Drop it onto any standard Mk4/AR15 lower receiver and you're ready to run.
Suppressor Compatibility and M-LOK Clearance
With a 1.72 inch internal diameter, the ZEROED handguard clears most modern suppressors. However, mounting M-LOK accessories in slots directly surrounding a tucked suppressor will significantly reduce internal clearance.
CMMG cannot guarantee the fitment of M-LOK accessories in these locations due to variances in suppressor and hardware sizes. Depending on your setup, modifying or shortening the M-LOK mounting screws may be required to prevent contact with your suppressor. Always verify clearance before use.
| Platform | Mk4 |
| Caliber | .300 BLK |
| Operating System | Direct Impingement |
| Barrel Length | 6.5 |
| Barrel Twist | 1:07 |
| Barrel Contour | MT |
| Barrel Material | 4140CM, Nitride |
| Muzzle Device | Faux Suppressor Blast Diverter |
| Muzzle Thread | 5/8 x 24 |
| Gas Port Location | Pistol |
| Gas Block | .750" Adjustable |
| Upper Receiver | Mk4 Billet 6061 T6 Aluminum |
| Hand Guard | 11" M-LOK (1.72" Inner Diameter) |
| Finish | Cerakote |
| Charging Handle | CMMG ZEROED Ambi |
| Weight | 3.9 lbs |
| Length | 18.6" |
