The Sentinel Design Glock Magwell is different from every other magwell that I know of for Glock handguns in that it is geared toward the LE/CCW market rather than competition. A magwell must be able to do the same thing for both markets, funnel the magazines into the magazine well quickly, but the LE/CCW crowd has additional requirements that this design attempts to address.
Overview
The Sentinel Designs Glock Magwell is designed to fit full size, small frame Glocks like the 17 and 22. It consists of 4 parts: a hard anodized aluminum grip plug with 2 threaded holes, a hard anodized aluminum magwell, and 2 screws. It comes with all necessary wrenches and thread locking compound is already applied to the screws.
Installation is very easy. After unloading and double checking your Glock, insert the grip plug into the channel at the rear of the grip. Install the set screw into the back of the grip plug through the Glock’s “lanyard” hole and tighten it until it is just flush with the surface of the back strap. Bolt the magazine well to the grip plug with the provided screw. The whole process takes about a minute.
Observations from Use
The Sentintel Designs Glock Magwell is a pretty ambitious product if you think about it. It is an attempt to provide most of what is great about magwell attachments for competition while mitigating the shortcomings of the typical magwell for self-defense shooters. Competition magwells are bulky, often prevent the use of standard baseplates, and prevent the user from being able to strip the magazine with their fingers in the event of a stuck magazine (double feeds, dirty magazine channel, etc).
The Sentinel Designs Glock Magwell directly addresses these shortcomings with a clever design that has obviously grown out of a lot of experience. When you use it, you can see how its design has clear roots in actual reloading techniques. There is a very clear understanding of how the reload is typically executed behind the design of the magwell. It tapers to from very thin at the front to thicker at the rear. This simple design adaptation is the key to most of the genius of this product.
The tapered design corrects 2 of the issues mentioned above for competition magwells used for self-defense purposes: it allows the use of a wide variety of baseplates including standard baseplates and actually allows the user to remove a magazine by allowing space to slip your fingers under the lip of the mag at the front of the grip. While there isn’t much of a funnel at the front of the grip to catch your mags, the magwell really doesn’t suffer much (if any) performance loss because most shooters train to index the magazine against the back of the magwell when reloading. The funnel is at its widest and most forgiving width toward the rear of the grip. See what I mean about a clear understanding of techniques?
The Sentinel Designs Glock Magwell also greatly reduces the bulk that is found on a typical competition magwell. It is barely wider than the grip itself. It only adds about .3″ to the overall width of the grip. It only adds about .2″ to the length of the grip. Even with the magwell installed, the longest part of your grip will still be the baseplate of the magazine. In practical terms, it leaves the concealability of the host Glock basically unchanged.
Magwells do not make slow shooters into fast shooters. In fact, you are unlikely to see much improvement in your reload times if you are not already fast enough to take advantage of a magazine well. I set up a simple drill to measure the benefits of the magwell for myself. The drill consisted of shooting 1 aimed shot, performing a slide lock reload, and firing another aimed shot to stop the timer. I did this drill for time 30 times with the magwell installed and 30 times without it installed over the course of 3 range visits. I fed the times into a spreadsheet and the results were interesting.
On average, I was just under .15 seconds faster with the magazine well installed. My fastest times were nearly identical at around 2.3 seconds. The biggest difference was with my slowest times. My slowest times with the magwell installed (2.6) were faster than my slowest times without the magwell (2.9) by a measurable margin.
What I think we can glean from this is that the real benefit of this magwell as it pertains to the self-defense shooter is not to make you faster but to make your reloads more sure under stress. It helps clean up the mess when you get sloppy. It would be very interesting to run these drills with additional stress (physical activity, noise, etc) included.
I have also found there is a slight ancillary benefit to using this (or really any magwell). The flared shape can help you place your hand on the grip more consistently and force you slightly higher on the grip. This is less pronounced on the Sentinel Design Magazine Well as it is on competition magwells simply because of the slim design but it is still noticeable.
I tested the Sentinel Design Glock Magazine Well with several baseplates including Dawson Extensions, Arredondo Extensions, Glock +2 Extensions, standard baseplates, and Vickers Baseplates. It worked with all them except the Vicker’s Baseplates. True compatibility with standard baseplates is fairly rare among Glock magwells. The Sentinel Design Glock Magazine Well isn’t just passable with the standard baseplates. It actually works very well.
The only beef I have with this magwell is that the grip plug could be shaped to better fill the half circle cutout at the back of the Glock’s magazine chute. As it is now, it leaves a bit of a ledge there. I never had a magazine catch on it so maybe it is a non-issue.
Wrap Up
I think there is a common misconception that magwells will make your reloads significantly faster. It can make you faster on average but if you are reloading under real stress, your reloads are likely to be anything but average.
The  biggest benefit to the magwell is seen when things go wrong. The magwell opening on a Glock is pretty large but it seems to get smaller under stress or when you are moving. The Sentinel Designs Glock Magazine Well can help make your gun just a bit more forgiving when your stress level requires that little extra margin for error. I think this is a tremendous piece of gear and I can’t wait until the G19 version is available.
Check out the Sentinel Design Glock Magazine Well at Austere Provisions Company.
