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CMMG, Inc AR-15 Receiver Extension and Stock Kit 55CA646 Buffer Tube Size: Mil-Spec, Length: 15 in, 17% Off w/ Free S&H

CMMG, Inc Fixed Butt Stock Kit, A1, 55CA646
CMMG, Inc Fixed Butt Stock Kit, A1, 55CA646
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CMMG, Inc Fixed Butt Stock Kit, A1, 55CA646

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Questions & Answers
Does the stock have the trap door like the original a1 stock Expert Answer

The CMMG, Inc AR-15 Receiver Extension and Stock Kit has a storage compartment in the rear of the stock.

by Hunter, Gear Expert, August 30, 2022
Will this fit my cmmg mk9 9mm carbine? And can I use the buffer I have in my ar or should I use the one that comes with the stock? Expert Answer

This CMMG, Inc AR-15 Receiver Extension and Stock Kit could be used with an MK9. The buffer that comes with the stock will need to be used.

by Hunter, Gear Expert, June 23, 2023
View All Q&A You Have a Question? Ask!
Customer Reviews
Helpful Positive Review
Awesome, hIghly recommended. by bic, Verified Owner, July 23, 2020
It looks and feels great perfect A1 stock with a butttplate that gives the look of an A2 stock. Color is a jet black infused nicely into the polymer giving it an extra touch of sheen and quality. Will definitely buy again.
5/5 found this helpful
Helpful Positive Review
Cmmg A2 stock by Bailey Gleason, January 4, 2021
Good quality easy to install stock the only thing it was missing was a QD sling mount which I fixed by purchasing a grovtec QD flush mount and installing it into the stock -drilled out tapped screwed in and epoxy. After that it’s a solid stock for th...
Read More...
1/1 found this helpful
Most Recent Reviews
Cheap immataion by Cory Johnson, Verified Owner, April 30, 2025
The stock is a cheap immataion, plastic copy. The stock is a thin hollow shell and the buttstock has a cheap, plastic trap door. I'm not happy with its construction.
0/1 found this helpful
Most Recent Reviews
Simple, well made, easy by M, Verified Owner, April 1, 2025
I bought this for a recent retro build. It fit perfectly and looks nice. Not much more to expect from it, and that's ok.
Most Recent Reviews
Meets Requirements by Dan, Verified Owner, February 1, 2025
I bought this for a retro-rebuild. I was looking for the usual: well-made, fit, installation, price, etc. It is exactly as described and what I wanted. I installed it in quick order, the fit is excellent, it's well-made, and it looks great! The price...
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Most Recent Reviews
M16 A-1 fixed stock. by Ezjtdoc, Verified Owner, January 11, 2025
Great fast delivery, the stock was very easy to install. The rifle looks like an original M-16 A-1 I went through basic training with, good retro look.
Read All 12 Reviews
Buffer Tube Size: Mil-Spec Length: 15 inCondition: New

Code: 2CM-FBS-CMMG55CA646-EE

MPN: 55CA646

UPC: 815835012636

List: $126.74Save 17%
$105.49

Product Info for CMMG, Inc AR-15 Receiver Extension and Stock Kit

Combine this kit with your choice of lower parts kit to complete your lower group.image

Features of CMMG, Inc Fixed Butt Stock Kit A1:

  • CMMG A1 Receiver Extension
  • Rifle Buffer Assembly
  • Rifle Action Spring
  • A1 Rifle length Butt stock Assembly

Package Contents:

  • CMMG, Inc Fixed Butt Stock Kit A1

Specifications for CMMG, Inc AR-15 Receiver Extension and Stock Kit:

Manufacturer: CMMG
Buffer Tube Size: Mil-Spec
Length: 15 in
Condition: New
Weight: 2 lb
Fabric/Material: Aluminum, Polymer

Package Contents:

  • CMMG, Inc AR-15 Receiver Extension and Stock Kit

CMMG, Inc AR-15 Receiver Extension and Stock Kit Orderable Models

List of Orderable Models

  • CMMG, Inc Receiver Extension and Stock Kit, A1, AR-15, 55CA646 , MPN: 55CA646 , UPC: 815835012636 , Code: 2CM-FBS-CMMG55CA646-EE

CMMG, Inc AR-15 Receiver Extension and Stock Kit Unavailable & Discontinued Models

List of Unorderable Models

  • USED CMMG, Inc Receiver Extension and Stock Kit, A1, AR-15, 55CA646, EDEMO2, Used, Condition Like New , MPN: 55CA646-EDEMO2 , Code: 2CM-FBS-CMMG55CA646-EE-EDEMO2
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