CMMG Banshee MK4 | .22 LR | 4.50″ Barrel | 22B5BD4AB

The CMMG Banshee MK4 upper group is an AR-platform .22 LR upper built on CMMG’s Mk4 platform. It features a 4.50-inch 4140CM SBN barrel with a 1:16 twist and operates via traditional blowback. This upper ships with CMMG ZEROED accessories including an ambidextrous charging handle, polymer dust cover and a ZEROED flash hider. It is designed to mate with any standard AR-15 lower and to use CMMG .22 AR conversion magazines.

Common applications for this upper include range training and recreational target shooting.

Product Specifications

• The manufacturer’s part number is 22B5BD4AB.
• The caliber is .22 LR.
• The barrel measures 4.50 inches.
• The barrel twist rate is 1:16.
• The barrel material is 4140CM SBN.
• The barrel contour is MT.
• The operating system is Traditional Blowback.
• The platform is Mk4.
• The upper receiver is machined from billet 6061 T6 aluminum.
• The handguard is a CMMG EML4 M-LOK free-float style finished in Armor Black Cerakote.
• The muzzle device is a CMMG ZEROED flash hider threaded 1/2 x 28.
• The charging handle is a CMMG ZEROED ambidextrous design.
• The overall length is listed as 12.8 inches.
• The finish is Black Armor Cerakote.
• The UPC is 810097502161.

This Banshee MK4 upper offers a compact, low-recoil .22 LR option for AR-platform users who want economical range time or dedicated practice with standard AR ergonomics. The combination of a short, durable 4140CM SBN barrel and a free-float M-LOK handguard supports accurate, consistent sighting and straightforward maintenance while keeping the package compact. Its ZEROED accessories make it a complete upper group ready for installation on a compatible lower.