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CMMG Mk3 ZEROED Gunbuilder's Lower Parts Kit
$130.02 $100.69 Save 23%
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Most Helpful Positive Review Lower parts that Rock.
Everything fits as they should. The saftey knobs are able to be set how you want them as in the angle. Very much would highly recommend. More than likely going to order a few more of these set ups for my next builds
Most Helpful Negative Review Mr. drcmcico
DO NOT BUY FOR AN AERO PRECISION LOWER RECEIVER!!! I’m Building an AR-10, 308 and purchased the CMMG LPK for 308. My lower receiver is an Aero Precion brand and the bolt catch does not work, and the magazine release is barely long enough. Soooo disappointed because it looks great.
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Easy simple and worked as it should.

by Slauer, Verified Owner from SC, United States Written on December 13, 2024
Kit was awesome, everything except pin for bolt catch worked(its a 25¢ roll pin) works wonders
Pros:
  • instructions
Cons:
  • Roll pin
Best Used for:
  • Dmps lower parts kit
Would recommend: Yes
Was it helpful to you? Yes | No

CMMG lower parts kit

by drcmcico, Verified Owner from OH, United States Written on September 10, 2024
Not for my aplication. CMMG lower kit will not fit on an Aero Precision 308 Lower. Do not waste your money or time!
Would recommend: No
1 of 1 found the following review helpful.
Was it helpful to you? Yes | No

Good LPK for an Aero M5 with some notes

by J, from CO, United States Written on June 3, 2024
Bought this for an Aero M5 build, for those looking to do the same be aware that the bolt catch will not work with the aero upper like stated in other reviews, but also be aware that the pivot pin is slightly too large in diameter and slightly too short. This makes it a bit hard to remove without a tool, but it will work. The takedown pin works fine and is removable by hand. I used a Phase 5 ambi bolt catch/release and will be ordering a BAD takedown pin set and keeping these as spares. It also does not have the set screw for the takedown pin under the grip, but that can be picked up a the hardware store. Other than that its a decently made kit for my first AR10 build.
Pros:
  • Parts that do fit fit well
Cons:
  • Some parts dont fit
Best Used for:
  • AR10
Would recommend: Yes
Was it helpful to you? Yes | No

CMMG zeroed

by Doug Foote, Verified Owner from OR, United States Written on March 10, 2024
Dropped in like butter. Add a drop-in trigger and this bad boy is ready to rock.
Would recommend: Yes
Was it helpful to you? Yes | No

MK3 Parts Kit

by Burnin Rubber, Verified Owner from TX, United States Written on February 17, 2024
Mil spec quality parts and the larger paddle bolt catch, ambi selector, and mag release are nice to have.
Would recommend: Yes
Was it helpful to you? Yes | No

Pretty good LPK

by oppressedbanana11, Verified Owner from NY, United States Written on January 20, 2024
I like that everything in here is good quality and made to spec. Love the ambi safety and mag release. Just beware the bolt catch won’t work with an Aero M5 receiver, too much material on the upper prevents proper range of motion. I’ll put it aside for a different 308 build. I still recommend this set.
Would recommend: Yes
Was it helpful to you? Yes | No

mk3 zeroed

by tefird64, from NC, United States Written on January 20, 2024
Good lpk, only issue I had was, with an aero M5 lower/upper, the bolt catch is a little too larger for the upper pocket. But otherwise everything else was a GREAT fit.
Would recommend: Yes
Was it helpful to you? Yes | No

great for 80% arms lower

by Johnny Mac, Verified Owner from SC, United States Written on November 6, 2023
Purchased this kit for my 80%arms lr.308 build. I was concerned about finding a kit that would be compatible, and this did the trick. My only complaint was the rod for the mag release was a little on the short side, but works well. Everything else was super smooth, and easy to install.
Would recommend: Yes
Was it helpful to you? Yes | No
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