AR-15 Upper Vice Block: Two Styles to Choose From

If you plan to do much work on an AR-15 rifle, you will (no doubt) find that it’s hard to do without a vice block. I use a lower vice block quite a bit when working on AR-15 rifles. But when I’m removing the barrel or doing much work to the upper receiver, an upper vice block is handy to have. Before I start discussing the common styles of vice blocks that I find helpful, I’d like to talk about the Real Avid Smart Fit Vice Block for a moment. It’s a handy tool to have, but it’s also good to know when a dedicated upper vice block would be better.

I’ve said many times before that the Real Avid Smart Fit vice block is one of my all-time favorite tools. The Smart Fit blocks are adjustable, so it fits in the magwell of your AR-15 perfectly. I leave the Smart Fit in my vice most of the time because it’s one of the most used tools I have. Set your AR-15 on the lower block and shazam, your rifle will stay in place while you work. Add optics, sights, or other accessories without trying to hold your rifle with one hand and work with the other.

Because it holds your AR-15 up so well, it’s easy to forget that it’s a lower vice block, not an upper vice block. I use the Smart Fit block for most applications on my rifle. But if you are removing/installing a barrel, an upper vice block is preferred.

Real Avid Lug Lock Upper Vice Block

Real Avid likes to make tools that are just different. In my experience, they always work as advertised and are almost always unique. The Lug Lock Upper Vice Block is the fastest upper vice block to use. Most others are made of two separate pieces, but with the lug lock, your upper receiver just slides over it. The end of the lug lock is made to fit into the chamber of the barrel, just like the bolt.

This locks the barrel and receiver together while you work. When tightening a barrel, the vice block helps keep pressure off the upper receiver. There is a red metal piece on the back of the lug lock that pulls off. There are two small pins in the back of the red piece that come out. After you place your upper over the lug lock, insert the red metal piece into the hole on the bottom of the lug lock to hold it in place (see photo above).

The other two pins fit into the holes on the flat side of the lug lock to keep it from rotating in the vice. One advantage of these two-piece upper vice blocks is that you can turn the upper receiver over and have access to the bottom of it from your vice. I use this feature often when installing handguards and need easy access to the bottom of the handguard.

VISM Upper Receiver Vice Block

There are several well-known upper receiver vice block manufacturers. The block I have used for years is a VISM because it was cheap. Wheeler makes one that is one piece that also works fine. Basically, you set your upper on it just like the lower and insert two pins to hold it on. The VISM vice block works by fitting a piece into the upper in place of the BCG. You then set the upper on the lower portion of the vice block and insert two pins to hold it in place (see photo below).

Using an upper vice block is best for building the upper receiver, changing out a barrel, or any other task that requires losing/tightening the barrel nut. You need a good vice attached to your workspace to clamp the vice blocks in place. Whichever style or brand of upper vice block you choose, the important thing is to find one that holds the upper receiver secure. When you are torquing a barrel nut down, you don’t want there to be a lot of play.

Even installing a forward assist can be annoying if the upper receiver moves back and forth while you are tapping in the pin. Otis makes a Pro AR-15 Lock Block that works a little like Real Avids Lug Lock. Both cost about $80, making the Real Avid system a better deal (in my opinion).

Having a Vice Block is a Lifesaver

Whatever brand you choose, having a slim design that slides into the chamber is nice when you are in a hurry and need to make a quick adjustment to something. You can also rotate the Real Avid Lug Lock in any direction to work on the top, bottom, or sides of the receiver and handguard. But I also want a solid vice block to attach with pins directly above the vice when I have a barrel that is difficult to get off.

I’m sure the Lug Lock would work fine in this case, too. But the VISM feels more solid when I’m cranking away on an old barrel nut. In reality, I use both the Lug Lock and VISM vice blocks regularly. If I were on a budget and had to pick just one upper and one lower vice block, I would stick with Real Avid. I have never been disappointed by their tools, and they work like they should.

If you plan to build your own rifle, I recommend buying an upper and lower vice block. The Real Avid Smart Fit lower receiver block and the Lug Lock upper receiver block are perfect tools for the job. If you want something different, try the VISM or Wheeler upper vice blocks. I may have my favorites, but they will all get the job done.

Other Tools to Consider

Besides getting a good set of vice blocks, set up your area with plenty of light. Consider putting a piece of carpet or something soft on the ground. This makes it easier to find those little parts when they go flying. Use a magnet to sweep over the carpet or soft surface. If a micro-sized spring hits the concrete floor, it’s a lot harder to find. A punch set, small hammer, torque wrench, and armor wrench are all must-haves, too. I built my first AR-15 with a few basic household tools so it can be done. But over the years, I have learned that life is much easier when you just get the right tool for the job.