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Reviews & Ratings for CMMG, Inc AR15 Lower Pins and Springs Parts Kit — 15 reviews

(15 reviews)
CMMG, Inc AR15 Lower Pins and Springs Parts Kit
CMMG, Inc AR15 Lower Pins and Springs Parts Kit
$14.95 $14.89
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Most Helpful Positive Review Good quality springs
For when your new build only needs the springs and detents. When all other components in the lower build have been upgrades and you only need the bare minimum or if you only need one spring but a whole extra set doesn't hurt for a couple bucks extra.
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CMMG spring and pins kit

by johnchip, Verified Owner from CT, United States Written on April 12, 2026
This spring kit is a step above an oops kit and is great to have in your spare parts box. Highly recommend.
Would recommend: Yes
Was it helpful to you? Yes | No
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Just Right but..

by Abraham, Verified Owner from CA, United States Written on June 16, 2025
Everything fits and its quiet compatible with MIL-SPEC lower but I was fitting this on a Aero Precision M4E1 Pro Ambi lower and I found that the Takedown pin's retention springs were just a couple of thousands thick to fit into it.
Pros:
  • Mil-spec
  • cheap and affordable
  • Genuine
Cons:
  • non-milspec incompat
Best Used for:
  • Mil spec Lowers
Would recommend: Yes
Was it helpful to you? Yes | No
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Springs and springs

by Jimbo, Verified Owner from NC, United States Written on June 15, 2025
Lots of spring in box. May have lost a detent or two. They shot across the room at Mach 3.6. Sadly they were lost to the vaccum monster. All user error had no problems 10/10 would loose a detent again.
Pros:
  • Spring
Cons:
  • None
Would recommend: Yes
2 of 2 found the following review helpful.
Was it helpful to you? Yes | No
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Worked for my CMMG MK9

by CZSeventy5, Verified Owner from PA, United States Written on August 20, 2024
I just needed two springs out of this kit and wasn't even sure these would fit. But they fit for the Takedown Pin spring and the Buffer tube retainer pin and retainer spring. So I am back in business.
Pros:
  • Universal fit
Cons:
  • None
Best Used for:
  • ar 15
  • MK9
Would recommend: Yes
Was it helpful to you? Yes | No
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Simple is Best

by BigPapa, Verified Owner from GA, United States Written on June 27, 2024
This kit finished My lower with a few extra parts that would be a hassle to buy separately. It’s priced well and the quality is more than adequate, especially when factoring in the price.
Pros:
  • Easy to install
  • well made
  • Simple
  • clean
  • intuitive packaging
Cons:
  • None
Best Used for:
  • Finishing that lower thats sitting there
Would recommend: Yes
Was it helpful to you? Yes | No
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Nice Option

by Ringinthesteel, Verified Owner from TX, United States Written on March 5, 2024
Has all the springs detents you need for your lower receiver.
Would recommend: Yes
Was it helpful to you? Yes | No
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Everything You Need

by Brian O, Verified Owner from OH, United States Written on December 2, 2020
If you like to build your own lowers then you probably know you need to have extra pins and springs because there is a 100% chance that you will loose something. Also, it is nice having spare's around in case something breaks.
Would recommend: Yes
Was it helpful to you? Yes | No
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Lower spring and pin kit

by Randy, from IN, United States Written on June 27, 2020
Excellent product, parts when into my M16 retro build wit no problems, perfect fit. Detents and prongs slid right in, I would highly suggest this kit just Incase you drop any. The price is very affordable
Would recommend: Yes
0 of 1 found the following review helpful.
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Great Product

by AE, from MD, United States Written on May 17, 2018
Easy to install. As described. Package and instructions made process simple. Product works great. Recommend highly. Will be using on future builds. Product looks great and have enjoyed using it. No issues using the product and hope to enjoy using it for many years to come.
Would recommend: Yes
0 of 1 found the following review helpful.
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Spare parts

by JC, from MO, United States Written on April 18, 2018
Never get mad when a spring shoots across the room when you have this kit around. Great for having around for when you lose a part, or just want to start a new build. And as always great customer service from the people at optics planet.
Would recommend: Yes
2 of 2 found the following review helpful.
Was it helpful to you? Yes | No
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