Editor's Note: Please view our Gen4 Glock photo gallery .

To say that Glock handguns are popular would be to damn these pistols with faint praise. Glocks are on the hips of more American law enforcement officers than any other make of gun. They're also popular with military forces worldwide. And a lot of civilian gun owners have a Glock or two in their collections. By any yardstick, the Glock line of handguns is hugely successful.

So why would Glock go and tinker with the ergonomics and interior works of its extremely popular firearms? That's the question that I asked myself when I first heard about the Gen 4 Glock G-17s and G-22s. So I had Glock send me some test and evaluation models so that I could compare them to the Gen 3 models in my collection.

There are three major improvements in the Gen 4 Glocks: switchable backstraps, more aggressive grip and slide texturing, and a double recoil spring. Let's give each of them a detailed analysis.

Improved Ergonomics

It's no secret that there are some shooters who just don't like Glocks. Maybe they are turned off by polymer-framed pistols. Maybe they prefer a hammer to a striker system. Maybe they just don't like the ergonomics of Glock pistols.

One reason I've found that some people don't like the ergonomics of Glocks is because they don't like the grip angle, and they feel it affects their point of aim. People who had problems using older model Glock pistols should give new Gen 4 Glocks a try.

The Gen 4s feature interchangeable backstraps that can be used to customize the dimensions of the grip and alter the reach to the trigger to fit the needs of individual operators. This is a very welcome improvement to the basic Glock and one that users have requested for some time, especially since just about every other major duty gun maker now offers firearms with this feature.

Each new Gen 4 Glock ships with three different backstraps. The small backstrap is factory installed, but shooters can easily replace it with a medium or large backstrap. The bottom line is that you get to choose which one of three grip sizes fits your shooting hand the best.  

A Better Grip

The interchangeable backstraps are just one of two major ergonomic improvements on the Gen 4 Glocks. Another new feature on the Gen 4s is more aggressive texturing on the grip and improved serrations on the slide.

The Gen 4 Glocks basically have an improved version of the recently introduced Glock Rough Textured Finish (RTF-2) models. This means the new Gen 4s have a very comfortable rubbery texture imbedded into the surface of the new grip that dramatically improves the feel. Gen 4 Glock pistols also have excellent north-south slide serrations that I believe are an improvement over the crescent shaped slide serrations that are used on the Rough Textured Finish (RTF2) Model Glock pistols.

Personally, I believe the new grip and slide serrations are the most important ergonomic improvements on these new models. I say this because I don't believe the interchangeable backstrap will be a big selling point for officers who already own Glocks. But the combination of the new grips and the slide with the interchangeable backstraps makes the Gen 4 a compelling revision of an already excellent firearm.

Soft Shooting

And as they say on those TV infomercials: Wait, there's more. Not only have the ergonomics of the Gen 4 Glocks been vastly improved. So have some of the interior components.

Some shooters have complained over the years that Glock's polymer frame pistols are so light that they have too much recoil, especially when firing snappy duty and self-defense ammunition. The Gen 4 Glocks use an ingenious new recoil spring design to make them shoot very softly.

The captive recoil spring system in the Gen 4 Glocks significantly dampens felt recoil. It also ensures that you have one less part to worry about when you disassemble your pistol in the field for cleaning and lubrication. 

By the way, if you are thinking of cutting corners by installing a Gen 4 captive recoil spring assembly into an older model Glock pistol, put that thought out of your head because the Gen 4 captive recoil spring assembly is not interchangeable with previous model Glocks.[PAGEBREAK]

Range Time

In all my years of shooting I can honestly say that I was never more interested in finding out how two particular firearms performed than these new Glocks. Since I am a huge fan of the 9mm Glock 17 I decided to field test the Gen 4 Glock 17 first.

I loaded a magazine with 124-grain FMJ Magtech ammunition and another with some 124-grain Federal Hydra Shok hollow-point, then I sent them down range with the greatest of ease. Next I fired some 124-grain Winchester FMJ ammunition and some 147-grain Federal Personal Defense hollow-point ammunition and again noticed no discernable recoil. But by far my favorite ammo to pump out of the Gen 4 G17 was some 9mm Federal 147-grain Flat Tip Metal Jacket ammunition. I swear that these rounds fired so smoothly from the Gen 4 that it felt like I was shooting a .22 LR pistol on steroids. 

But so far we hadn't really given the new recoil spring a workout. So my shooting buddy handed me a Gen 4 G17 magazine filled with Plus P and Plus P Plus ammo. I have to admit that I wasn't thrilled with the idea of shooting these snappy rounds. I have bad arthritis in my hands and powerful rounds can make shooting very unpleasant.

But I wanted to test the new recoil system, so I started banging away. A smile a mile wide crossed my face. I could not believe that I was firing a Glock 17 with the snappiest 9mm ammunition on the market and pain in my hands wasn't forcing me to stop. For me to be able to shoot Plus P and Plus P Plus ammo from a Glock 17 without pain is an outright miracle. 

I decided to press my luck and loaded the .40 caliber Gen 4 Glock 22. As soon as I started pulling the trigger my eyes rolled in amazement as I realized that this pistol was noticeably softer shooting than a standard Gen 3 or earlier model Glock 22.

On another range session I found that the Gen 4 Glock 17 was also soft shooting with 24-grain Speer Gold Dot hollow-point ammunition, a rather snappy type of standard velocity 9mm ammunition that normally produces substantially more felt recoil in my earlier generation "regular model" Glocks.

I also tested the Gen 4 Glock 22 with a mixture of 155-grain Speer Gold Dot hollow-point ammunition, 165-grain Winchester Ranger Bonded hollow-point ammunition, and 180-grain Winchester Ranger hollow-point ammunition. It was connect-the-dots accurate and very comfortable to shoot. For the rest of my evaluation, I used 180-grain Federal FMJ and 180-grain Winchester FMJ ammunition. I even tried some extremely long range shooting and was amazed at how well the new Gen 4 Glock 22 with night sights performed.

Making Adjustments

Once both pistols were tested to see how they performed using the "standard" or small grip, it was time to do some shooting with the other backstraps. To install a medium or large grip all you have to do is clip the bottom of the grip extension to the bottom of the small or standard grip, then use the extra roll pin that comes with the pistol to secure the larger grip extension to the pistol by inserting the pin into the hole near the top of the small grip. Trust me, this is very easy to do.  

Before I sat down to write this review, my shooting buddies and I tested each pistol using different grip extensions to see how each pistol felt while being test fired with different ergonomics. In the end I opted to carry the Gen 4 Glock 17 with the standard or small grip, which is smaller in overall size than the standard grip on a Gen 3 or earlier full-size Glock service pistol.

You should also know that the medium interchangeable grip extension makes the Gen 4 Glock have the same grip dimensions as a Gen 3 or an earlier model Glock grip, while the large grip extension is dimensionally the same size as that of a Glock 21. But I should point out that even though the dimensions might be the same, the large grip extension on the Gen 4 pistol feels a little better in my hand than the grip on a standard model Glock 21. I chalk this up to the fact that the Gen 4 has a soft rubbery texture to the grip portion of its frame. As for the reach to the trigger I had absolutely no problem using any of the grip options offered with the Gen 4 Glock pistols.

I had no problem shooting the Gen 4 Glock 22 with all three grips, but I decided to install the large extension grip on this pistol so my strong hand had more to hold onto to absorb the recoil energy of the .40 S&W ammunition. The combination of the large grip and the recoil capture spring combine to make the Gen 4 G-21 a pleasure to shoot even with my arthritic hands.

With their much improved recoil systems and excellent ergonomic features, these Gen 4 Glocks are truly outstanding duty guns. I believe the Gen 4s will be a grand slam for Glock and armed professionals and that legally armed citizens who currently use full-size Glock pistols will upgrade.

I like these pistols so much I have decided to sell my standard model previous generation Glock pistols so I can afford to buy a 9mm Gen 4 Glock 17 and possibly even a Gen 4 Glock 22.  All I need now is for Glock to start manufacturing a Gen 4 Glock 19, a Gen 4 Glock 23, and a Gen 4 Glock 34.

Nick Jacobellis is a medically retired U.S. Customs Agent and former New York police officer who was physically disabled in the line of duty while working undercover as a federal agent.

Find out more about the Glock Gen 4 G-17 and G-22 .