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CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit Up to 10% Off w/ Free Shipping — 2 models

CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group BCG Kit, 8 inch SBN Barrel, Black, 99D517A
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group BCG Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group BCG Kit, 8 inch SBN Barrel, Black, 99D517A
1 of 14 images
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group BCG Kit, 8 inch SBN Barrel, Black, 99D517A
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group BCG Kit, 16 inch SBN Barrel, Black, 99DE642
2 of 14 images
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group BCG Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
3 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
4 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
5 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
6 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
7 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
8 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
9 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
10 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
11 of 14 images
CMMG, Inc Barrel and Bolt Carrier Group Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
12 of 14 images
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
13 of 14 images
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642
14 of 14 images
CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit, 16 inch SBN Barrel, Black, 99DE642

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Questions & Answers
Will this work in any other 9mm AR style rifle such as a Foxtrot Mike? Expert Answer

No, not without modification. Most 9mm lower receivers have the ejector built into the receiver, as standard Glock and Colt compatible 9mm carriers have no ejector. The CMMG bolt has the ejector built into the bolt (similar to a .223 bolt), so it will not work with a lower that has the ejector.

by Ethan C., Gear Expert, November 3, 2019
See 6 More Answers
CMMG describes that this kit is designed to function with their MkG series lowers. Will this kit work in a stock upper/lower? Expert Answer

Yes, you can use a milspec upper and lower receiver with this kit.

by Ethan C., Gear Expert, November 3, 2019
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review Works Great by Gromit, January 24, 2019
I shoot steel matches and have been using the typical blow back 9mm PCC. Once tuned, they work good as long as you keep them clean and don't mess around with the PF too much. To use the CMMG setup I installed the 9mm CMMG upper on my AR15 lower (st...
Read More...
13/22 found this helpful
Helpful Positive Review Best pistol cal option available by Padden, April 24, 2020
I installed this kit in a mil-spec (recommended by cmmg) upper to use with cmmg’s arc-9 mags. A little over 400 round through it so far in various weights and manufacturers including browning 125 round nose, Winchester white box, and 147 Remington. 1...
Read More...
5/6 found this helpful
Helpful Positive Review My AR9 build by Blue-collar, September 19, 2020
I pick up this CMMG both barrel kit to build my AR9. I pick the 8 inch barrel. High quality, the Bolt and bolt carrier group is perfect. They have a spring behind the bolt and a round cam pin. It’s a little different but other than that it is perfec...
Read More...
3/4 found this helpful
Helpful Positive Review Reliable and Light on Recoil by BB, Verified Owner, September 23, 2020
I built the 8" kit into an Aero Precision Receiver/Handguard, Stealth Recoil Spring, and SB PDW brace. Out of 500 rds, we had one failure to eject, but the round sounded weak when fired, so we weren't surprised. No squip, fortunately. The recoil is l...
Read More...
9/10 found this helpful
Helpful Positive Review CMMG 8" barrel/bolt by Jerbear, Verified Owner, December 9, 2018
If you're looking into buying this, you know what you're looking at. You're attempting to build a PCC with certain characteristics that a direct blowback gun uses heavy buffers & springs to control. Well, it works! It's lighter than your typical blow...
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28/36 found this helpful
Helpful Negative Review In concept great, in practice, meh.. by Ricky Bobby, April 10, 2019
Bought the 8". First bolt self destructed. At first Customer Support said the wear was normal. The bolt had chunks on the leading edge of the bolt missing. This is after 300 rounds. I sent pictures after multiple calls, I sent photo's and they r...
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57/66 found this helpful
Read All 15 Reviews
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Product Info for CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit

Our MkG GUARD Barrel and BCG Kit allow you to build a Pistol Caliber Carbine using our Patent Pending Radial Delayed Blowback System. Unlike typical direct blowback systems, our RDB uses a bolt that is forced to rotate and unlock, slowing the BCG. This results in a lighter BCG for a lighter rifle, and less felt recoil than a straight blowback system.image

Our MkGs Barrel and Bolt Kits are designed to work exclusively with our MkGs Lowers. Other manufacturers lowers may work, but we cannot guarantee function or reliability. Buy a new 9mm AR barrel today!

Specifications for CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit:

Manufacturer: CMMG
Color: Black
Finish: Salt Bath Nitride
Fabric/Material: 4140 Chrome Moly
Caliber: 9mm Luger
Gun Model: CMMG MkG-45 Guard
Threads per Inch: 1/2x28
Barrel Twist Rate: 1-10
Condition: New

Package Contents:

  • CMMG, Inc MkG Guard 9mm Barrel and Bolt Carrier Group Kit

What firearm models does the manufacturer say CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit is compatible with?

The manufacturer suggests that CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit is compatible with CMMG MkG-45 Guard

CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit Orderable Models

List of Orderable Models

CMMG, Inc Barrel and Bolt Carrier Group BCG Kit, 9mm, 16 in, Salt Bath Nitride, Black, 99DE642 , MPN: 99DE642 , UPC: 815835019819 , Code: 2CM-BCG-BBCGK9-99DE642
CMMG, Inc Barrel and Bolt Carrier Group BCG Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A , MPN: 99D517A , UPC: 815835019802 , Code: 2CM-BCG-BBCGK9-99D517A

CMMG, Inc 9mm Barrel and Bolt Carrier Group (BCG) Kit Unavailable & Discontinued Models

List of Unorderable Models

DEMO, CMMG, Inc Barrel and Bolt Carrier Group BCG Kit, 9mm, 16 in, Salt Bath Nitride, Black, 99DE642-DEMO , MPN: 99DE642-DEMO , Code: 2CM-BCG-BBCGK9-99DE642-DEMO
DEMO, CMMG, Inc Barrel and Bolt Carrier Group BCG Kit, 9mm, 8 in, Salt Bath Nitride, Black, 99D517A , MPN: 99D517A-DEMO , Code: 2CM-BCG-BBCGK9-99D517A-DEMO
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