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Questions & Answers
Does this 5.7, 5” upper come with any magazines? Expert Answer

The CMMG Banshee Upper Receiver Groups do not come with magazines.

by Hunter, Gear Expert, June 26, 2023
so this upper can shoot 9mm rounds right? Expert Answer

The CMMG Banshee Upper Receiver Group models 99B518D-AB, 99B17FD-AB, and 99B518D-AB-DEMO are chambered in 9mm.

by Hunter, Gear Expert, November 13, 2023
Customer Reviews
Helpful Positive Review
CMMG 9mm Upper.. by Benjamin Hunter, Verified Owner, October 24, 2022
This Shoots So Smooth. We have (2) 9mm uppers for AR Pistols Wife - PSA 4 inch barrel - Nice Mine - CMMG 5inch barrel - No Comparison between!! So Smooth & No Problems.. Mounted on Anderson AM15 Lowers
2/2 found this helpful
Most Recent Reviews
CMMG Banshee 9mm complete upper by George, Verified Owner, June 30, 2025
Received it quick, this CMMG upper looks great, believe it is a quality product. Haven’t shoot it yet, just temporary mark 5 stars for its appearance and quality looks. Will add more comments later.
Most Recent Reviews
Pretty awesome! by Bradizzler, Verified Owner, June 18, 2025
I purchased this to go onto a Silencer Co lower with a tax stamp to make an SBR. So far I have only had 1 feed malfunction out of 1250 rounds from 4 different manufacturers. It seems like the cerakote could be a little thicker, but it still looks awe...
Read More...
Most Recent Reviews
CMMG Banshee 9mm Upper by BB, Verified Owner, May 13, 2025
Great upper, plug and shoot on my ar15 lower with cmmg 9mm magazines. Great product and well worth the price. The radial delay reduced felt recoil significantly compared to direct blow back 9mm ar uppers I have shot before.
Read All 4 Reviews
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Product Info for CMMG Banshee Upper Receiver Group

Gaining more acceptance as the go to personal defense caliber for many shooters in recent years, 5.7x28mm has proven itself to be well suited for the job. With incredibly flat shooting performance and low recoil, 5.7x28 excels at closer ranges while still providing ideal penetration. Equipped with a 5 barrel, this is the most compact 5.7x28mm upper group CMMG offers. CMMG 5.7x28mm uppers are designed to work with CMMG Mk57 lowers or standard AR15/Mk4 lowers (when used with 5.7 AR Conversion Mags).image

WARNING: California`s Proposition 65

Specifications for CMMG Banshee Upper Receiver Group:

Manufacturer: CMMG
Barrel Length: 8 in
Barrel Profile: Medium Taper
Threads per Inch: 1/2x28
Muzzle Device: CMMG Zeroed Linear Compensator
Color: Armor Black
Fabric/Material: Billet 6061 T6 Aluminum
Gun Rail: M-LOK
Gun Type: Rifle
Gun Make: AR Platform
Gun Model: Universal
Condition: New
Magazine Included: No
Mount Type: M-LOK

Package Contents:

  • CMMG Banshee Upper Receiver Group

CMMG Banshee Upper Receiver Group Orderable Models

List of Orderable Models

  • CMMG Banshee Upper Receiver Group, 9mm, 8in, Armor Black, 99B518D-AB , MPN: 99B518D-AB , UPC: 810097505643 , Code: 2CM-URC-CMK5728-99B518D-AB
  • CMMG Banshee Upper Receiver Group, 5.7x28mm, 8in, Armor Black, 57B88BD-AB , MPN: 57B88BD-AB , UPC: 810097504387 , Code: 2CM-URC-CMK5728-57B88BD-AB

CMMG Banshee Upper Receiver Group Unavailable & Discontinued Models

List of Unorderable Models

  • DEMO, CMMG Banshee Upper Receiver Group, 9mm, 8in, Armor Black, 99B518D-AB , MPN: 99B518D-AB-DEMO , Code: 2CM-URC-CMK5728-99B518D-AB-DEMO
  • DEMO, CMMG Banshee Upper Receiver Group, 9mm, 5in, Armor Black, 99B17FD-AB , MPN: 99B17FD-AB-DEMO , Code: 2CM-URC-CMK5728-99B17FD-AB-DEMO
  • DEMO, CMMG Banshee Upper Receiver Group, 5.7x28mm, 8in, Armor Black, 57B88BD-AB , MPN: 57B88BD-AB-DEMO , Code: 2CM-URC-CMK5728-57B88BD-AB-DEMO
  • USED CMMG Banshee Upper Receiver Group, 9mm, 5in, Armor Black, 99B17FD-AB, EDEMO1, Used, Condition Like New , MPN: 99B17FD-AB-EDEMO1 , Code: 2CM-URC-CMK5728-99B17FD-AB-EDEMO1
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