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Car-15/M4 Buttstock Wrench - M4 Buttstock Wrench
Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.
$69.99
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SKU: 080000670
Overview
Built for installing and removing collapsible carbine buttstocks, this wrench is designed to engage M4-type receiver extension nuts with full, non-slip contact across all four notches. Its dedicated fit helps direct torque to the nut during tightening or removal, while also reducing the chance of damage from slippage. The tool adds a pry blade/screwdriver, a 1/2" square torque drive opening, a fixed stock receiver extension remover, and a hanging hole for storage. Made by Brownells with hardened steel and a black oxide finish, it is suited to armorers and serious shooters working on current-model M4-type setups.
Why Hunters Choose the Brownells
Four Precision-machined
M4-type receiver extension nuts
Transfers Torque
Directly to the nut for
Includes Pry
Blade/screwdriver, 1/2-inch square torque drive
Heavy-duty Steel
Hardened, black oxide finish
Fits Current-model
Four square notches
Key Features
- Four precision-machined teeth engage all four notches in an M4-type receiver extension nut.
- Designed for easy removal and installation of collapsible carbine buttstocks.
- Transfers torquing force to the nut to help avoid damage from wrench slippage.
- Includes a pry blade/screwdriver, 1/2-inch square torque drive opening, and fixed stock receiver extension remover.
- Built from a single piece of steel with a hardened black oxide finish.
- Includes a handle hole for hanging on a pegboard.
Best Used For
- For armorers installing or removing collapsible carbine buttstocks on current-model M4-type receiver extension nuts.
- For shooters who want full, non-slip engagement when working on four-notch receiver extension nuts.
- For bench use where torque is applied through the nut rather than risking slippage on the extension tube.
- For users who value added utility from a pry blade, screwdriver, and 1/2-inch square torque drive opening.
- For organized workspaces needing a hangable wrench kept ready on a pegboard.
Specifications
| Blade Finish | black oxide |
|---|---|
| Blade Steel | hardened |
| Compatibility | Fits current-model M4-type receiver extension nuts with four square notches |
| Construction | heavy duty steel construction |
| Features | four precision-machined teeth; pry blade/screwdriver; 1/2 in square torque drive opening; fixed stock receiver extension remover; hanging hole in handle |
| Overall Length | 7-1/8 in (18.1 cm) |
| Thickness | .312 in |
Pros
- Four precision-machined teeth provide full engagement with M4-type receiver extension nuts.
- Transfers torque directly to the nut for installation and removal tasks.
- Includes pry blade/screwdriver, 1/2-inch square torque drive opening, and fixed stock receiver extension remover.
- Heavy-duty steel construction with hardened, black oxide finish.
- Fits current-model M4-type receiver extension nuts with four square notches.
- Handle includes a hanging hole for pegboard storage.
Considerations & Trade-offs
- Fits current-model M4-type receiver extension nuts with four square notches, so it is not a universal stock wrench for every platform or nut style.
- The tool is purpose-built for collapsible carbine buttstocks; users working on other stock systems will need a different wrench.
- At 7-1/8" long, it offers leverage in a compact tool, but it is still a dedicated bench tool rather than a multi-purpose field tool.
- The added pry blade/screwdriver, torque-drive opening, and fixed stock receiver extension remover increase versatility, but they also make the wrench more specialized than a simple single-function tool.
Suggested Comparisons
- AR-15/M4 armorer tools
- Carbine buttstock installation and removal tools
- Receiver extension nut wrenches
- Firearm maintenance hand tools
Suggested Accessories
- Armorer's wrench
- Torque wrench
- Pegboard hook
- Gun vise
Frequently Asked Questions
What is this wrench designed to do on an M4-type carbine stock assembly?
It is designed to engage the receiver extension nut for easy installation and removal of collapsible carbine buttstocks.
What type of receiver extension nut does it fit?
It fits current-model M4-type receiver extension nuts with four square notches.
What features are included besides the main wrench function?
The tool also includes a pry blade/screwdriver, a 1/2" square torque drive opening, a fixed stock receiver extension remover, and a hanging hole in the handle.
What is the wrench made from?
The provided specifications list it as steel with a hardened, black oxide finish.
How long is the wrench?
The specifications list the wrench at 7-1/8 inches (18.1 cm) long.