The CMMG BANSHEE 5.7x28mm 8" upper receiver group delivers a compact, high-performance foundation for building a personal defense weapon or PDW-style AR. This 5.7x28mm upper is engineered for the modern shooter who wants to leverage the cartridge's reputation for controllable recoil and effective terminal performance in a short-barreled platform. Whether you're assembling a dedicated PDW or adding a specialized upper to your AR collection, the BANSHEE brings proven engineering and real-world usability to the table.

Built on a billet 6061 T6 aluminum upper receiver with a 1:9 twist barrel, this upper cycles via radial delayed blowback operation—the same system that makes the 5.7x28mm cartridge run reliably in compact form factors. The 8-inch 4140CM SBN barrel is contoured for balance and equipped with CMMG's ZEROED linear compensator (1/2 x 28 thread) to manage impulse and keep your sight picture steady. The included bolt carrier group arrives ready to run, and you get a ZEROED ambi charging handle and dust cover to round out the package.

The CMMG EML7 M-LOK handguard gives you modern accessory mounting without unnecessary weight, while the whole assembly tips the scales at just 2.9 lbs. The upper runs on either a CMMG Mk57 lower or a standard AR15/Mk4 lower (when paired with CMMG 5.7 AR conversion magazines), giving you flexibility in how you complete the build. Available in black Cerakote, this is a no-nonsense upper for shooters who value compact form factor and reliable function over mall-ninja aesthetics.

The CMMG BANSHEE 5.7x28mm 8" upper receiver group delivers a compact, high-performance foundation for building a personal defense weapon or PDW-style AR. This 5.7x28mm upper is engineered for the modern shooter who wants to leverage the cartridge's reputation for controllable recoil and effective terminal performance in a short-barreled platform. Whether you're assembling a dedicated PDW or adding a specialized upper to your AR collection, the BANSHEE brings proven engineering and real-world usability to the table.

Built on a billet 6061 T6 aluminum upper receiver with a 1:9 twist barrel, this upper cycles via radial delayed blowback operation—the same system that makes the 5.7x28mm cartridge run reliably in compact form factors. The 8-inch 4140CM SBN barrel is contoured for balance and equipped with CMMG's ZEROED linear compensator (1/2 x 28 thread) to manage impulse and keep your sight picture steady. The included bolt carrier group arrives ready to run, and you get a ZEROED ambi charging handle and dust cover to round out the package.

The CMMG EML7 M-LOK handguard gives you modern accessory mounting without unnecessary weight, while the whole assembly tips the scales at just 2.9 lbs. The upper runs on either a CMMG Mk57 lower or a standard AR15/Mk4 lower (when paired with CMMG 5.7 AR conversion magazines), giving you flexibility in how you complete the build. Available in black Cerakote, this is a no-nonsense upper for shooters who value compact form factor and reliable function over mall-ninja aesthetics.