How To Use Brownells AR-15/M16 Barrel Extension Torque Tool

The Brownells AR-15/M16 Barrel Extension Torque Tool

1. Install the barrel into the upper receiver.

2. Tighten the barrel nut onto the rife’s upper receiver with just your fingers.

3. Firmly mount the barrel nut wrench in a bench vise.

4. Slide the upper receiver assembly (with its barrel nut facing down) onto the wrench, making sure that the barrel nut engages the wrench properly.

5. Insert the Brownells AR-15/M16 Barrel Extension Torque Tool into the rear of the upper receiver until its teeth lock into the locking lugs of the barrel extension.

6. Attach a ½-inch torque wrench to the rear of the tool and torque the barrel nut to the handguard manufacturer’s recommended torque specifications.

7. Make sure to align the gas tube port so there is clearance for the gas tube.

What Does It Do?

The Brownells AR-15/M16 Barrel Extension Torque Tool allows armorers to apply the correct amount of straight-line torque to the barrel nut without the risk of scratching the exterior of the upper receiver. It allows for quick and easy barrel nut installation and removal without stressing the rifle’s upper receiver and its takedown pinholes.

RELATED STORY: 7 Steps To Using Brownells’ AR-15/M16 Upper Receiver Lapping Tool

This tool helps maintain proper alignment of the barrel, upper receiver and gas tube ports and can be used with many barrel nut wrenches, AR-15/M16 armorer’s wrenches or free-floating tube wrenches and a ½-inch square drive torque wrench. It also requires a solidly mounted bench vise.

How Do You Use It?

Scroll through the gallery above for a step-by-step look.

Does It Work?

In a nutshell, yes, it does—but with a limitation. This tool is not suitable for all types of barrel nuts because it works by interlocking the barrel’s nut on a barrel nut wrench that is then secured in a bench vise. The type of barrel nut wrench your handguard requires dictates whether or not you can use this tool effectively. We found that handguards that are installed after the barrel nut is secured to the upper receiver can usually benefit from this tool the most. As an added bonus, this tool allows for plenty of leverage when removing stubborn barrel nuts, especially delta ring assemblies.