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CMMG AR-15 A1 Receiver Extension and Stock Kit

Manufactured by CMMG
SKU: 55CA646
MPN: 55CA646
Manufactured by CMMG
3 Reviews

In Stock

Orders of non-FFL items will ship same day if ordered before 3:30pm CST (M-F). FFL orders will ship within 5 business days if transfer details are provided.

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The CMMG AR-15 A1 Receiver Extension and Stock Kit is a fixed A-frame style stock for a new build or replacing a factory stock. The A1 stock measures around 10.25" and has a fixed configuration to provide ultimate stability while shooting. Its design is simple and dependable, with a storage compartment at the rear of the buttstock and a loop for sling attachment. Its high-strength polymer construction provides maximum durability without needing a foam-filled core. The kit also includes a CMMG A1 receiver extension buffer tube, AR-15 rifle buffer, and AR-15 rifle action spring.

  • 10.25" A1 rifle-length buttstock
  • CMMG A1 receiver extension buffer tube
  • AR-15 rifle buffer
  • AR-15 rifle action spring
  • Sling mount
  • Rear storage compartment
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Compatible Make
Compatible Model
StorageInternal Storage
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to www.P65Warnings.ca.gov.

Ratings & Reviews

3 reviews

  • 4 stars
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  • 3 stars
  • 0 reviews
  • 1 star
  • 0 reviews

Fast shipping and great quality

by -

Haven't installed this kit yet, but I am very pleased with the quality of the items in this kit.


by -

Want your ar to look like m16 get this stock looks great and works great.

CMMG's worst product

by -

I've used various CMMG parts over the years and have had no complaints with their function, fit or finish. In this case, this stock doesn't meet the quality I would expect from a CMMG product. The stock polymer has sharp flashing from the mold that needs to be removed prior to use, the rear plate of the stock doesn't align with the stock itself so there are some exposed sharp edges due to the poor part alignment. In addition the latch on the storage door is very flimsy and doesn't feel like it will last any longterm use. It's more of a thin tab then any of the other A1 style stocks I've used in the past. The rear plate of the stock also wasn't fully textured as the stock image shows, I know A1's are not fully textured, but the listing image throws off any expectations.

If you're looking for a fixed A1 style stock, I would recommend looking else where for something with better fit and finish.