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GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER
GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER
GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER
GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER
None
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CMMG - AR-15 Gunbuilder's Lower Parts Kit

34 Reviews
AR-15 Gunbuilder's Lower Parts Kit
Brownells #
100014538
MFR #
55CA601
UPC
815835015408
$29.74 $34.99
Coupon Code
Purchase Limit Help

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International purchase information

Specifications
Make Model Fit:
AR-15.Universal
Quantity:
1
Restriction
Gun Part Restrictions:
Yes
Prop 65 restriction:
Warning! Cancer and Reproductive Harm. Www.p65warnings.ca.gov
View US State Restrictions
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International purchase information

What is the CMMG - AR-15 Gunbuilder's Lower Parts Kit?

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.

Gun Part Restriction
Gun Parts have restricted shipping to CA.

Prop 65WARNING: Cancer & Reproductive Harm - www.P65Warnings.ca.gov

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GUNBUILDER'S LOWER PARTS KIT FOR AR-15 LOWER REVIEWS

4.6
34 Reviews
5 Stars
82%
4 Stars
9%
3 Stars
3%
2 Stars
0%
1 Stars
6%
Reviews Summary
Customers consistently appreciate the GUNBUILDER'S LOWER PARTS KIT for its quality, ease of installation, and organized packaging. Many highlight its value without unnecessary components. However, some have reported issues with specific parts like the safety selector and fitment on certain lowers. Overall, it's a reliable choice for those customizing their AR builds.
What Reviewers Are Saying
Product Quality
82%
The quality of the parts is consistently praised across reviews. Many users find the machining and finish excellent, noting that the parts function smoothly and fit well in various lower receivers. However, a few reports indicated problems with specific parts, such as the safety selector not meeting expectations.
Organization and Packaging
75%
Reviewers commend the organized packaging of the kit, which includes labeled compartments, making assembly much easier. This thoughtful packaging helps prevent mix-ups and assists beginners, enhancing the overall building experience.
Customization Flexibility
68%
Many users appreciate that the kit omits components they may not need, such as grips and triggers, allowing for a more personalized build. This flexibility is a significant advantage for experienced builders looking to select their preferred parts.
Ease of Installation
71%
The installation of parts is generally described as straightforward, with reviews noting that the fit is tight yet manageable. Users have shared positive experiences with assembly, aided by the clear part labeling and organized layout.
Value for Money
70%
A significant number of reviews highlight the kit as a cost-effective option, providing high-quality parts at a reasonable price. Many customers have compared it favorably against other kits, feeling it delivers robust performance without extraneous costs.
Occasional Quality Control Issues
16%
Though many reviews are positive, a few customers reported specific quality control issues, particularly with individual parts like the safety selector or inconsistent fitment. This indicates that while the overall product quality is high, there may be occasional variations.
5
AR-15 parts
Worked as advertised.
by William McShane on March 30, 2026
Verified Purchase
Was this review helpful? 0
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
by SCOTT ADAM on February 05, 2026
Verified Purchase
Was this review helpful? 0
5
Quality set
I ordered this for a Wilson Combat lower build. The parts were all quality parts and had no issues. Will definitely buy this again for the next build as well as stocking spare parts.
Would you recommend this? Yes, I would recommend to a friend
by MARC JACKSON on September 23, 2025
Verified Purchase
Was this review helpful? 1
5
Awesome product
Cmmg parts are some of the best you can buy. I really like how the parts are packaged.
Would you recommend this? Yes, I would recommend to a friend
by George Wain on January 05, 2025
Verified Purchase
Was this review helpful? 1
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
by Paul on October 03, 2024
Was this review helpful? 0
View All 34 Reviews
Customer Questions
4 Questions