Umarex Glock 17 Gen4 Part 5

Umarex Glock 17 Gen4 Part 5

Authenticity, Velocity, Accuracy

By Dennis Adler

About as close to matching a GTL equipped Glock 17 Gen4 as you can get. This is a Glock GTL 22 tactical light and red laser mounted on the new Umarex Glock 17 Gen4. Every detail from the inside out makes this air pistol a winner right out of the gate.

The ultimate test of any CO2 model based on a centerfire gun is its absolute authenticity to duplicate the handling of its cartridge firing counterpart, thus making the CO2 model a worthwhile investment as a training substitute. But among the features that must match is the use of the same holsters, duty gear (magazine pouches for example), and accessories. In the case of the Glock 17 Gen4, that includes the full range of backstraps available as well as mounting tactical lights and laser sights made for the centerfire pistol. Beginning with the Umarex Glock 19 Compact, the standard Glock GTL system of tactical lights and light/laser combinations fit that gun, and each succeeding Umarex Glock model up to the Gen4. But the Gen4 also incorporates the interchangeable backstrap design. The CO2 model comes with the two standard backstrap panels originally developed for the Glock 17 Gen4 model. Since that time two additional designs have been introduced and are sold with the centerfire Glock 17 Gen4, medium and large backstraps with an extended beavertail. These come with the current guns and are also sold separately to retrofit earlier Gen4 models. The question is will they fit the Gen4 CO2 model? Sadly, the answer is no.

The one thing the CO2 model can’t duplicate is the exact grip frame width of the centerfire model. The Umarex Glock is about 0.0625 inches wider. Not much, but just enough that the Gen4 backstrap panels, sold as a separate item for the older Gen4 models that did not come with the extended beavertail backstraps, won’t line up to the cross pin holes. Bottom line, you can’t use the Gen4 centerfire pistol’s backstraps on the CO2 model. Sorry to break the news for those of you entertaining the thought of using your Gen4 backstraps on the CO2 model.

The CO2 model’s grip frame is just slightly wider (by about 1/16th of an inch), enough that the holes will not align and the extended beavertail backstraps will not go on. They are of course, not made for the CO2 model only the 9x19mm Glock, and while this is not essential to the CO2 model’s role as an understudy, if you have big hands this is the only disappointment with the Gen4 CO2 model, but it answers the question about “absolute” authenticity. Everything else, holsters, tactical lights and tactical light/laser combinations will fit the CO2 gun. So we move forward with the final test of the Umarex Glock 17 Gen4 at 10 meters to see if it can maintain the same level of accuracy as the Third Gen at that range. Remember, the Third Gen with its short, short-recoil blowback action is sending BBs downrange at well over 360 fps, compared to the Gen4 which is averaging 317 fps. The additional 12 feet from 7 yards to 10 meters, generally sees a drop off in accuracy with blowback action pistols in the 300 to 320 fps velocity range.

The Third Gen model at 10 meters does a good job of grouping shots tight. This is 18 rounds spread out over the A-Zone of an IPSC cardboard silhouette. Best 5-shot group measured 0.75 inches.

Find a Hawke Scope

10 meter test        

Firing at 1-second intervals using a Weaver stance and two-handed hold, the Third Gen Glock 17 put 18 rounds into a total spread of 2.125 inches all inside the A-Zone of an IPSC cardboard silhouette target, just above the A. The best 5-shot group measured 0.75 inches. Switching to the Gen4 Glock 17, I again shot a full magazine using the same stance and hold. My 18 shots covered 2.43 inches all inside the A-Zone with a best 5-shot group at 0.81 inches. Close enough that the Gen4 can almost match the higher velocity Third Gen at 10 meters.

With a full blowback action design that you can fieldstrip like a centerfire Glock 17, the Umarex Glock 17 Gen4 can’t match the Third Gen’s higher velocity, but it can shoot just about as well out to 10 meters. Best 5-shot group measured 0.81 inches.

Combat test

I ran a combat drill with the Third Gen Glock 17 test, firing double taps at 15 feet to 21 feet, single weak hand shooting at 21 feet, dropping and kneeling shots, rolling sideways and firing from floor level shots, 10 meter shots two-handed, drawing and rapid firing while moving toward the target from 21 feet to 15 feet, and two barricade shots single handed right and left hands. Everything hit inside the 9, 10 and X rings with multiple overlapping hits. This proved that the Umarex Glock could work for basic training drills with immediate feedback from the target to gauge accuracy from different shooting positions. With the Gen4 I used another IPSC silhouette target and repeated the same combinations. This required a reload and my total spread for 22 shots, all inside the A-Zone area, measured 5.5 inches x 3.875 inches.

So right now it would appear that the Umarex Glock 17 Gen4 is the gun to own…but what about this? What about the best new gun before the Gen4 came out, the Air Venturi Springfield Armory XDM 4.5? As the Magic 8 Ball used to say, “Ask again later.”

Overall, this is better than the Third Gen test which had a total spread of 7.25 inches x 5.5 inches. Either way, both CO2 models make it possible to do reliable shooting drills from 15 feet out to 10 meters that are commensurate with 9mm drills at the same distances. That the Gen4 can deliver this level of accuracy firing off hand at 1-second intervals with only an average of 317 fps vs. 376 fps for the Third Gen, tells us that this latest offering from Umarex and Glock meets all the standards for a CO2 understudy (despite not fitting the Gen4 beavertail backstraps), and moves to the top of the list for overall authenticity for a blowback action CO2 BB pistol. The Gen4 is a must have air pistol for Glock enthusiasts. Ah, but what about its closest competitor, the Air Venturi Springfield Armory XDM 4.5?

To be continued…

A word about safety

Blowback action airguns provide the look, feel and operation of their cartridge-firing counterparts and this is one reason why they have become so popular. Airguns in general all look like guns, blowback action models more so, and it is important to remember that the vast majority of people can’t tell an airgun from a cartridge gun. Never brandish an airgun in public. Always, and I can never stress this enough, always treat an airgun as you would a cartridge gun. The same manual of operation and safety should always apply.


7 thoughts on “Umarex Glock 17 Gen4 Part 5”

  1. Too bad the actual backstraps don’t fit the C02 pistol. If Umarex & GLOCK thought these things through better, they would have taken that into consideration. Other than that, I think it’s a home run for Umarex.

    Without the beavertail, do I need to worry about a slide bite? I have the Umarex PPKs, and that little sucker does nip me. I have the beavertail on my Gen5 9mm for that reason. I don’t have large hands, so it’s more of a precaution than anything.

    • I wouldn’t think you have to worry about it, the beavertail on the grip frame itself is pretty big. I remeber my first Colt Model 1911 .45 ACP back in the early 1970s, a WWII gun, and it took a bite out of my hand the first day at the range. You learn quickly…but I think you are safe with the Gen4.

      • Thanks for the info. I think I’ll get one for my brother’s birthday then I can try it out. Great recent issue of “Guns of the Old West” by the way. I wonder if Henry will roll out that side gate in “Big Boy” pistol calibers(.45 Colt please). Don’t have much of a range where I shoot, so a .38-55 isn’t much good to me.

  2. Dennis,

    An excellent series on this highly-anticipated air pistol. In Part 3 you commented that the trigger reset was slightly shorter on the CO2 Gen4 than on the CO2 Gen3. I am not a Glock CO2 or firearm owner, but for those who are thinking of the CO2 Gen4 as a potential training aid for the 9×19 counterpart, how does the air pistol’s trigger reset compare to that of Glock firearms?

    Again, excellent series.


    • Michael:
      I feel it is pretty close with the Gen4 CO2 model. The G17 Third Gen CO2 is not a great trigger, but the Gen4 is very well done and at 5.5 pounds average, right up to spec with the centerfire gun. The reset is shorter on the 9mm but not by much. Umarex and Glock did a great job with the Gen4.


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