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CMMG, Inc MK9 Buffer Assembly
$43.49 $41.46 Save $2.03
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9mm buffer

by Roger, from SC, United States Written on July 12, 2018
I used this bolt carrier group in a 9.5" barrel AR pistol build with a Faxon 9mm SAAMI barrel, it ran flawlessly and cycled quickly and smoothly. This was Colt-SMG 9mm build rather than a Glock magazine build, however this will work for Glock magazine 9mm builds as well. I used a 9mm carbine buffer with a JP Enterprises .308 buffer spring, recoil was negligible allowing for extremely rapid repeated shots, all placed within an inch at 75 feet (the max distance possible at the range I was at) using flip up iron sights. I'm a left-hand shooter and even without a 9mm ejection port dust cover, casings did not hit me, they were ejected straight to the side. Very happy with this bolt carrier group
Would recommend: Yes
Was it helpful to you? Yes | No

Perfect Fit

by Niko, from TX, United States Written on February 24, 2018
This was an exact replacement for the CMMG 9mm. OpticsPlanet had fast shipping and the best price. Great product and great service! I was happy with the purchase. I wish the weight for 9mm carbine buffers was standardized upon because with so many different weights on the market it's easy to get confused.
Would recommend: Yes
Was it helpful to you? Yes | No

Works well

by Michael, Verified Owner from FL, United States Written on December 20, 2017
Nicely made buffer that works great in my 9mm AR build. Slows down the cyclic rate enough to use some pretty hot ammo without any malfunctions. Would highly recommend it to others building a 9mm rifle.
Pros:
  • heavy
  • Work as advertised
Cons:
  • None
Best Used for:
  • 9mm ar
Would recommend: Yes
Was it helpful to you? Yes | No
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