CMC Triggers AR-15 Lower Parts Kit - No Fire Control Group or Grip

Manufactured by CMC Triggers
SKU: 81500
MPN: 81500
Manufactured by CMC Triggers
23 Reviews

In Stock

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With roots in aerospace manufacturing, CMC is perhaps best known as the producer of the original drop-in precision trigger for the AR-15/10 platform. CMC Triggers are dedicated to crafting the finest parts and accessories for law enforcement, our military, and civilian use.

The AR Lower Assembly Kit contains MIL-SPEC components, perfect for your next AR-15 build or keep one on hand for spare parts.

100% Manufacturers Lifetime Warranty!

NOTE: Fire control group and pistol grip not included.

Kit includes:
  • (1) Bolt catch
  • (1) Bolt catch plunger
  • (1) Bolt catch roll pin
  • (1) Bolt catch spring
  • (1) Buffer retainer
  • (1) Buffer retainer spring
  • (1) Magazine catch
  • (1) Magazine release button
  • (1) Magazine catch spring
  • (1) Standard safety selector
  • (1) Safety selector detent spring
  • (1) Safety selector detent
  • (1) Takedown pin
  • (1) Pivot pin
  • (2) Takedown/pivot pin detents
  • (2) Takedown/pivot pin springs
  • (1) Trigger guard
  • (1) Trigger guard roll pin
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BrandCMC Triggers
Weight3.2 Oz
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

great parts

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Got this kit on sale and it worked great.everything fit and assb quick and painless ..Will buy again

Minor issues, slight quality complaint but fitment is good.

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Giving this kit 3 stars. Most things in it are of acceptable quality. I didn't use all of them but they appear to be sound. I installed about half of the kit on a new lower. Fit is good. The description indicates "mil-spec" though. The trigger guard is made of plastic which is out of spec. I replaced that with a better one after install. The other issue I had was with the buffer retention pin which the nub snapped off the top of and now serves no function. In its defense, I was clamping a pistol buffer (9oz) down on a carbine spring to loosen it while inside the buffer tube. When I hit the clamp release the 9 oz buffer sprung forward and slammed the nub off the buffer retention pin. If the pin was of high quality it would not have broken like that.
From PA: The kits we have in stock have Aluminum trigger guards. SOunds like you might have a mispack from the factory. We'd be happy to get you the correct trigger guard.

Great Low Parts Kit

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Great value! I didn't have any problems using this LPK. I prefer to buy them without the grip and fire control group. It is a good idea to have some extra parts on hand and I like to pick these up when they are on sale. They store easily and come in a thin small box with the parts in small plastic bags.

Another Plastic Trigger Guard

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While this looks like a great LPK, I have not installed it, as I'm waiting to pick up my Aero Precision receiver pair from my FFL tomorrow.

However, just as another receiver pointed out, I too received a plastic trigger guard. Now, while the description doesn't say what material is used, nor does the CMC website, I thought it important to make it clear that this other reviewer's experience was not a one-off.

I hate to ask for an exchange because I got a great Thanksgiving deal on this LPK, and it otherwise appears to be high quality. However, I'm doing a fairly high-end build, and I don't plan on relying on the plastic trigger guard to protect my quite expensive CMC trigger on a high-end build.

YMMV, and you may receive an aluminum trigger guard, but at least two reviewers have received plastic ones: I had a higher expectation of quality from CMC.


by -

Pure garbage. I am severely in this CMC Ar-15 complete lower parts kit. The trigger guard is out of spec and will not fit in my lower. Also the pin that holds the bolt catch wont fit and got stuck in my lower. I had to pull it out with pliers and the pin broke. The lower I am using is a Bravo Co

Lower parts kit

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Everything fit well in Anderson lower has a plastic trigger guard not the one pictured.

Great parts kit!

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All parts fit well and function great!!

Tigger Guard


I’d give it 5 stars because the kit itself is flawless, but I also got a plastic trigger guard and I just purchased with the Independence Day sale. No fault of Primary Arms at all. It’s a good thing I like Gucci trigger guards and am going to replace it anyway.

2 pivots, no take down

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Seems decent except I was given two pivot pins and no take down pin in the kit, instead of one of each.

Missing a detent pin

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Mine came missing a detent pin :(. Not really a big deal but annoying none the less