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AR-15/M4 Stock Wrench
AR-15/M4 Stock Wrench
AR-15/M4 Stock Wrench
AR-15/M4 Stock Wrench
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ROCK RIVER ARMS - AR-15/M4 Stock Wrench

76 Reviews
AR-15/M4 Stock Wrench
Brownells #
739000010
MFR #
AR0165
UPC
842834100804
$5.99
Coupon Code
Purchase Limit Help

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Standard Shipping Estimated Delivery
Estimated delivery: Sep 25
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Specifications
Material:
Steel
Color:
Black
Quantity:
1
Item Length (Inches):
7.625
Make Model Fit:
AR-15.Universal
Restriction
Gun Tool Restriction:
Yes
View US State Restrictions
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What is the ROCK RIVER ARMS - AR-15/M4 Stock Wrench?

ROCK RIVER ARMS AR-15 M4 STOCK WRENCH

The AR-15 / M4 Stock Wrench is an essential AR-15 armorer's tool designed for the installation, removal, and maintenance of M4-style collapsible stock assemblies and receiver extension components. Built to provide secure engagement with castle nuts and buffer tube hardware, this specialized wrench helps firearm builders, armorers, and gunsmiths perform stock-related tasks with confidence and precision.

Whether assembling a new rifle, replacing a buffer tube, or performing routine maintenance, this durable stock wrench provides the leverage and control needed to properly tighten and remove critical components. Its purpose-built design makes it an indispensable addition to any AR-15 gunsmithing toolkit.

FEATURES

  • Designed for AR-15 and M4-style stock systems
  • Installs and removes castle nuts
  • Supports receiver extension and buffer tube maintenance
  • Provides secure engagement with stock hardware
  • Durable construction for long-term use
  • Delivers improved leverage during installation and removal
  • Ideal for AR-15 assembly and maintenance
  • Compact design for easy storage
  • Suitable for gunsmiths, armorers, and firearm enthusiasts
  • Helps ensure proper stock installation
  • Rifle receiver extension torque to 35-39 foot pounds
  • Carbine receiver extension nut torque to 38-42 foot pounds

SPECIFICATIONS

  • Application: Stock Installation and Maintenance
  • Compatibility: M4-Style Collapsible Stock Systems
  • Use: Assembly, Repair, and Customization
  • Construction: Heavy-Duty Steel
  • Parkerized finish.
  • 7-5/8" (19.3cm) long.

CUSTOMER INSIGHTS

Customers frequently praise the wrench for its simple, effective design and dependable performance when installing or removing castle nuts. Many users appreciate having a dedicated tool for stock work, noting that it provides better engagement and control than improvised solutions. Owners also highlight its durability and value as a must-have addition to an AR-15 maintenance kit.

The AR-15 / M4 Stock Wrench is a practical and reliable tool for maintaining, upgrading, and assembling AR-15 rifles equipped with M4-style collapsible stocks. Offering secure castle nut engagement, durable construction, and easy operation, it provides the functionality needed to perform stock and buffer tube work efficiently and confidently.

See all of our AR15s and AR15 parts here.

Gun Tool Restriction
Gun Tools have restricted shipping to CA.

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AR-15 M4 STOCK WRENCH REVIEWS

3.8
76 Reviews
5 Stars
50%
4 Stars
16%
3 Stars
9%
2 Stars
14%
1 Stars
11%
Reviews Summary
The AR-15 M4 Stock Wrench offers mixed reviews. While many appreciate its affordability and sufficient performance for occasional users, several noted durability issues with the material and fit. Some customers reported it worked well for simple tasks, but others faced complications with tighter bolts, recommending better quality tools for frequent use.
What Reviewers Are Saying
Product Durability
45%
Many reviewers express concerns about the low durability of the wrench, highlighting issues with bending, stripping, and breaking after limited use. Several users suggest that for those frequently working on ARs, a more robust tool would be necessary.
Ease of Use
60%
Several reviews praise the wrench for its simplicity and ease of use. Users have found it effective for basic tasks like installing and removing castle nuts, especially when approached with the right technique. However, some users warn that it requires careful handling to avoid slipping and damaging components.
Value for Money
50%
Positive remarks frequently mention the wrench's affordability, making it a suitable option for occasional users or beginners. However, several users caution that the low price reflects the quality, suggesting that more demanding tasks may require investing in pricier alternatives.
Quality Control Issues
35%
Numerous reviews pointed out inconsistencies in manufacturing, including poorly manufactured notches that resulted in improper fitting. This theme suggests a need for better quality control to ensure all tools perform as expected.
Comparison to Higher-End Tools
40%
Reviewers often compare this budget wrench to more expensive options, highlighting that while it may suffice for light tasks, it falls short in durability compared to premium alternatives. Users with extensive experience recommend investing in a higher-quality tool for regular use.
5
Fantastic Value
Hard to beat the price for this quality wrench!
Would you recommend this? Yes, I would recommend to a friend
by DAVID H. on June 04, 2026
Verified Purchase
Was this review helpful? 0
5
AR Stock Wrench
Excellent wrench for the price. Made the build go so much smoother. I recommend it. The rest of this is to meet the character minimum.
Would you recommend this? Yes, I would recommend to a friend
by AL C. on December 08, 2025
Verified Purchase
Was this review helpful? 0
5
Great Castle nut wrench
For the price, you cannot beat it. I have purchased several of these over the years and given them as gifts to my friends getting into guns.
Would you recommend this? Yes, I would recommend to a friend
by PW on April 21, 2025
Was this review helpful? 1
5
No lower
No lower
by RIC S. on March 26, 2025
Verified Purchase
Was this review helpful? 0
5
Nice little tool
I bought this when I bought the folding stock adapter so I could work on my AR-15. I was surprised at how heavy and thick it was and good quality for the price. Worth the money to work on your AR.
Would you recommend this? Yes, I would recommend to a friend
by VALENTIN S. on June 23, 2024
Verified Purchase
Was this review helpful? 1
View All 76 Reviews
Customer Questions
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