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Questions & Answers
whats the metal grade ? Expert Answer

This is made of 416 Stainless Steel.

by Kurt Colbourne, Gear Expert, September 27, 2021
What is the specs of gas block and gas tube for this kit?

The CMMG is rotary delayed blowback and does not use a gas tube.

by Ethan, Verified Owner, September 5, 2021
Color: Black Finish: Matte Caliber: 5.7x28mm Barrel Length: 8 inAdditional Features: Threaded Dimensions: 1.90 X 12.65 X 18.70 in

Code: 2CM-ATB-57D18B1

MPN: 57D18B1

UPC: 816422029129

Product No Longer Available

Product Info for Cmmg, Inc Cmmg Barrel W/bolt Kit 5.7x28mm 8" Rdb Black

The 5.7x28mm Barrel and BCG Kit allows you to build an AR in 5.7x28mm using CMMG's patented Radial Delayed Blowback operating system. Unlike typical direct blowback systems, Radial Delayed Blowback not only reduces the weight in your BCG but it results in less felt recoil than a straight blowback system. CMMG's 5.7x28mm Barrel and Bolt Kits are designed to work with either a CMMG Mk57 lower receiver or with a standard AR15 lower receiver (when using CMMG 5.7 AR Conversion Magazines).image

Package Contents:

  • Cmmg, Inc Cmmg Barrel W/bolt Kit 5.7x28mm 8" Rdb Black

Ammunition

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  • Cmmg, Inc Cmmg Barrel W/bolt Kit 5.7x28mm 8'' Rdb Black , MPN: 57D18B1 , UPC: 816422029129 , Code: 2CM-ATB-57D18B1
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