Glock 20 10mm Review

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Glock 20 10mm Review

Are you considering purchasing a Glock 20 in 10mm Auto? If so, you’ve come to the right place. 

There are few pistols in the world that come with the reliability, simplicity, and versatility of the Glock Model 20. It excels as a home defense pistol and as a sidearm to have while hiking or hunting out in the woods.

There are a lot of pistols that I love, and some that I enjoy shooting more than the Glock 20. But when it comes to sheer practicality, I can’t think of very many handguns that I would take over it. 

In this guide, we’ll dive into the history of the 10mm Auto’s development, and the pros and cons of the Glock 20.

Development of the 10mm Auto

It’s impossible to talk about the Glock 20 without also talking about the cartridge that it’s designed for, the 10mm. After all, the 10mm cartridge is the whole reason to get the Glock Model 20 in the first place. 

The 10mm Auto was developed by Jeff Cooper in the mid 1980s, largely for the new Bren-Ten pistol that was released at the same time. Several of you reading this may already know the story, but for those of you who do not, we’ll dive into it anyway. 

The 10mm was envisioned by Jeff Cooper as a round that could offer superior stopping power than the 9mm and superior range and trajectory than the .45 ACP. At the time, these were the two most common semi-automatic pistol cartridges in the United States.

The FBI had replaced their .357 Magnum and .38 Special revolvers with Smith & Wesson semi-automatic pistols in 9mm. While reliable and high quality, the pistols proved to have stopping power issues at the infamous 1986 shootout in Miami. 

The FBI agents involved in this shootout found themselves outgunned as the 9mm rounds had poor results in bringing down the robbers. This led the Bureau to search for a new round that offered superior ballistics and stopping power than the 9mm, but greater capacity than the .45 ACP.

This led the FBI to eventually adopting the 10mm Auto as developed by Jeff Cooper. While short-lived as a service cartridge, the 10mm would gain a small but noticeable following that has expanded over the years. 

The 10mm Auto is unique because it offers the same high energy and flat trajectory as a magnum revolver cartridge. It’s for this reason that the round is often compared to the .357 Magnum. However, the round is also short and rimless, so it can work in a semi-automatic pistol’s magazine. 

For these reasons, many people think of the 10mm Auto as offering the stopping power of a .357 Magnum with the capacity of a 9mm. That’s not too far from the facts, and it was my biggest reason for buying a Glock Model 20 in the first place. 

The 10mm was short lived as the FBI’s service caliber due to the high recoil it produces. The round was cut down into the .40 S&W, which was then adopted by the FBI and law enforcement units all over the country until the last few years when departments have begun to switch back to 9mm.

But the 10mm has endured and today the cartridge is more popular than it ever has been. The Glock 20 became Glock’s fourth pistol released to the marketplace in 1991; still in regular production today, it holds the distinction of being the longest living 10mm pistol continuously produced.

Other notable 10mm handguns, include the Colt Delta Elite (essentially the 10mm version of the Colt Series 80 1911), Springfield XDM 10mm, SIG P220 in 10mm, Ruger SR1911 in 10mm, Ruger GP100 in 10mm, the Bren Ten pistol, and the EAA Witness Carry.

However, the Glock 20 has easily emerged as the most popular and bestselling 10mm pistol on the market today. It’s not hard to see why. 

The Versatility of the Glock 20

I would argue that the Glock 20 is the most versatile pistol that you could own. Let’s examine the specific arguments behind this statement, which I don’t make lightly. 

The 10mm is a highly versatile round because of the fact that:

  1. It’s effective against both people and dangerous animals for self-defense
  2. Due to the narrow diameter, pistol magazines chambered for the round can carry a lot of bullets 

Remember that the 10mm Auto offers trajectories and ballistics on par with the .357 Magnum. Now imagine having 15 rounds of .357 Magnum rather than the 5 or 6 rounds of a revolver (in addition to spare magazines that facilitate faster reloads than speedloaders).

For these reasons, it’s not hard to see why many hunting guides in North America are reliant on the Glock 20 in 10mm for defense against wild animals such as wild boars or brown bears. 

The 10mm also excels as a defensive round against people who may seek to harm you as well. The 10mm may be more narrow than the .45 and therefore theoretically create a more narrow wound channel, but it also generates over 1.5x the amount of chamber pressure that the .45 does. 

In other words, the 10mm Auto will hit harder and penetrate further than the .45 will. It has more energy at one hundred yards than the .45 ACP produces at the muzzle. 

A Glock 20, loaded with 15 rounds of 10mm defensive loads, is a formidable home defensive pistol, tactical sidearm, or a tool for bear protection. 

The Glock 20 Today

As of the time of this writing, Glock has not yet released the Glock 20 in the Generation 5 configuration. If you want a Glock 20, you’ll have to settle for a Generation 4 or a Generation 3 model.

The Generation 4 is the current production model for the Glock 20. It comes with finger grooves on the front of the frame, removable backstraps, a reversible magazine catch, a durable recoil spring, and more aggressive texturing on the frame so you can more easily grasp it in slippery conditions.

If a Generation 5 version of the Glock 20 is ever released, we can expect it to likely have the same features that are present on the Generation 5 Glock 17, 19, or 22. In other words, an improved trigger pull, no finger grooves on the front of the frame, an ambidextrous slide stop lever, a marksman’s barrel for improved accuracy, and a flared magazine well for easier reloads.

Pros and Cons of the Glock 20 

In all honesty, there are only three real cons to the Glock Model 20: it’s big, the ammo can be expensive, and it delivers what certain people may consider to be too much kick. 


  • 15 round magazine capacity 
  • Very reliable
  • Very simple to operate 
  • Easy to field strip 
  • Effective against both people and dangerous big game
  • Very versatile (suitable for home defense, tactical use, or defense in the wild) 


  • Large size is not the best for concealed carry 
  • Recoil may be to excessive for some people 
  • 10mm ammunition is usually more costly than 9mm Luger or .45 Auto

Just keep in mind the Glock 20 is not a concealment piece nor was it ever meant to be one. It was meant from the beginning to be a duty sidearm or as a defensive piece for when you venture out into the wilderness. 

In these roles, the Glock 20 absolutely excels.   


All of this isn’t to say that the Glock 20 is officially the greatest handgun ever made; but it is definitely one of the most pragmatic. 

As a Glock, the Model 20 is reliable, simple, practical, and durable. As a 10mm, it’s effective as a defensive tool against people and dangerous animals alike. 

It may be a big pistol and not the best for concealed carry, but if you want something that’s good at just about anything else you need a handgun for, it’s hard to not recommend the Glock 20. 

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