GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER

GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER Reviews & Ratings

CMMG® Lower Parts Gunbuilder's Kits contain the needed parts to complete an AR-15 lower receiver. These kits come less the trigger, grip and trigger guard.

INCLUDES:
  • Takedown pin
  • Receiver pivot pin
  • Takedown pin detent (2)
  • Takedown pin detent spring (2)
  • Hammer and trigger pin (2)
  • Safety selector
  • Selector detent
  • Magazine catch
  • Magazine catch spring
  • Magazine release button
  • bolt catch
  • Bolt catch plunger
  • Bolt catch spring
  • Bolt catch spring pin
  • Buffer retainer
  • Buffer retainer spring

See all of our AR15s and AR15 parts here.

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5 Stars
92%
4 Stars
8%
3 Stars
0%
2 Stars
0%
1 Stars
0%
Reviews Summary
Customers are highly satisfied with the GUNBUILDER'S LOWER PARTS KIT, praising its quality, fit, and value for money. Many enjoy the convenience of labeled parts, making assembly easier, and appreciate the ability to customize their builds. A few wished for more options like an ambidextrous model, but overall feedback is overwhelmingly positive.
What Reviewers Are Saying
Product Quality
92%
Reviewers frequently highlight the superior quality of the parts, noting excellent machining and finish. Many assert that every component functions flawlessly, contributing to a reliable build experience.
Ease of Assembly
75%
Numerous customers mention the simplicity of assembling the kit, especially praising the labeled packaging that aids even beginners. Many highlight their success in building ARs using this kit without any issues.
Customization Options
42%
Several reviews express satisfaction with the kit's flexibility, particularly the absence of standard parts like a trigger and grip, allowing users to choose their own. Reviewers appreciate this approach as it saves money and enhances personalized builds.
5
AR-15 parts
Worked as advertised.
5
Worked great
All parts there. All parts fit. All parts function. Worked great.
Would you recommend this? Yes, I would recommend to a friend
5
Top notch kit
Good quality at a reasonable price. No parts that may not be used like a pistol grip or mil spec trigger.
Would you recommend this? Yes, I would recommend to a friend
5
Parts replacement
Worked perfectly. Very pleased with the quality of the product at this price point.
5
Solid parts kit
This is second time of used this kit for a custom build. Quality mil spec parts from trusted manufacturer at a great price.
5
Good Kit, great value
I used this kit to complete my retro lower. First time I've built and AR, and all these parts fit my Brownells lower perfectly. Functions well, I recommend this kit.
5
" Great Kit - Great Cmpany "
Have used many CMMG build kits and Complete lower parts kit on many different receivers, have never had a problem with either of the kits, the complete lower kit has the parts come in colored bags for easy identification, the build kit has every part marked so if you mess up it's usually the fault of the operator and not the parts...
5
Works well, good packaging
All parts fit an Anderson lower as expected. The fact that the parts are separated and labeled in the packaging helps since most of us using the kit don't do this every day. So far function is just fine. Great option if you already have a separate trigger. Don't forget that the trigger guard is not included. Recommend the pivot pin detent install tool from brownells or something comparable as it really makes the task easier. Also recommend copious use of masking tape to protect surfaces while building.
5
Preferred Build Kit
Built 5 lowers with this type of kit, every one a success. There is a label for every part in the packaging so it is easy to use for even beginners. Follow Brownells How-To video and you cannot go wrong. Selector switch is closest design next to the ones I used to get issued. Solid "click" between Fire/Safe, unlike some others I've seen. No stock pistol grip or trigger, which is nice to be able to customize with your own. Besides those 2 items, just need the extension tube, castle nut, end plate, buffer spring, buffer, and stock of your choice on your stripped lower and you're half way home.
5
Good kit
very easy to assemble, parts fit like a glove, I have used several different kits while building ar's this is by far the best kit i have used!