The CMMG Banshee Upper Group is a compact AR upper assembly chambered for 5.7x28mm with an 8-inch barrel. It ships complete with a bolt carrier group and ZEROED-branded accessories for installation on compatible lowers. The upper is designed for PDW-style configurations and is compatible with CMMG Mk57 lowers or a standard AR-15/Mk4 lower when used with CMMG 5.7 AR conversion magazines.
Key Specifications
- The chambering is 5.7x28mm.
- The barrel length is 8 inches.
- The barrel twist is 1:9.
- The barrel contour is MT.
- The barrel material is 4140CM SBN.
- The operating system is Radial Delayed Blowback.
- The muzzle device is a CMMG ZEROED Linear Compensator and the muzzle thread is 1/2 x 28.
- The upper receiver is Billet 6061 T6 Aluminum.
- The handguard is the CMMG EML7 M-LOK.
- The finish is Cerakote Standard and the package weight is 2.9 lbs with an overall length of 16.5 inches.
This upper provides a compact, ready-to-install platform for PDW-style or range-oriented builds. It combines CMMG components and ZEROED accessories to deliver a straightforward, low-profile installation option for shooters assembling a 5.7x28mm AR configuration.
This description was generated with AI and may contain errors. Verify specifications and legal restrictions with the manufacturer before purchase. Provided “as-is” without warranties or guarantees.




