Product Spotlight: Brownells AR15 Upper Receiver Vise Block

Hey everyone, Caleb and Steve here from Brownells. Today, we’re excited to show you a brand-new tool for AR builders—the Brownells AR-15 Upper Receiver Vice Block. If you’re serious about assembling, maintaining, or upgrading your AR, this new block is designed to make your life a lot easier.

What You Will Learn

By watching this video, you’ll learn how to properly use the new Brownells AR-15 Upper Receiver Vice Block—a tool designed to securely hold your AR-15 upper while you install parts, perform maintenance, or build a new rifle. The video walks through step-by-step installation, highlights its internal support wings for added strength, and explains the best use cases for the block.

Benefit 

Watching this video will help you avoid common mistakes, protect your receiver from damage, and make your gunsmithing projects safer and more efficient.

A New Vice Block for Upper Receivers

We’ve shown some lower receiver vice blocks recently, but this time we’re focusing on the upper receiver. This new block is specifically designed to hold an AR-15 upper securely in your vice while you work. It’s lightweight, simple to use, and incredibly effective for building and maintaining AR-pattern rifles.

What Caleb’s working with in the video is a BRN-4 upper, our HK416 clone, but this block is fully compatible with any standard AR-15 upper.

Installing the Block

Installation is super straightforward:

1. Start by removing the two pins from the block.
2. Insert the winged portion of the block into the upper receiver.
3. Make sure the “front” label is facing the right way—it’s even marked clearly on the block.
4. Align the pin holes and push the pins through.

If the pins don't slide in easily, just apply a little extra pressure—they’re designed to fit snugly. Once everything is locked up, you're ready to secure the block into your bench vice.

Securing Your Upper for Work

Once clamped, the upper receiver is held firmly in place, allowing you to work on:

• Installing barrel nuts

• Installing muzzle devices

• Mounting optics and accessories

• General upper receiver maintenance

Steve points out that the block is strong enough for general torque jobs, but if you’re trying to remove a severely over-torqued barrel nut or muzzle device, you should use a more specialized setup like a clamshell or a device-specific fixture.

The Strength Advantage: Internal Support Wings

One of the big improvements on this new block compared to other designs is the internal wing structure.

When you insert the block into the upper, wings inside the receiver help absorb and distribute torque loads across the interior of the receiver, rather than putting all the stress on the front and rear lugs.

This reduces the risk of damaging or snapping your upper receiver when applying normal assembly torque.

Steve points out that he’s seen lugs break on uppers before—and it was usually because the builder used the wrong block or applied crazy high torque levels (hundreds of foot-pounds) without proper support. This block design helps protect against that.

When to Use Extra Caution

Again, if you're dealing with something that's seriously over-torqued from the factory or from a previous install, it’s smart to move to a clamshell device or device-specific upper receiver fixture to avoid damage.

For most standard builds, upgrades, or routine installs, though, this Brownells block is more than strong enough.

Final Thoughts

If you’re planning a new AR build or just want a more secure, hassle-free way to work on your upper receivers, the new Brownells AR-15 Upper Receiver Vice Block is a no-brainer.

It’s:

• Lightweight

• Simple to install

• Strong enough for most common gunsmithing tasks

• Compatible with standard AR-15 and BRN-4 uppers

And, like Steve joked, the only thing it doesn’t come with is a giant coffee cup—but everything else you need to make your workbench more efficient is here.

If you have any questions about the block or anything else AR-related, feel free to drop a comment or give us a call on the Brownells Tech Line.

Thanks for watching, and we’ll see you next time!

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