Definitive Guide to Glock 17 Gen. 4

Replica pistols, by definition, should be 1 to 1 clones of the guns they replicate. Umarex has gone to great lengths to make this a reality with their Glock airguns. The Glock 17 G4 has the same dimensions, weight, switches, and slide as you'll find on the real deal. The polymer material feels good in the hand, the same feeling you would get from the Glock 17 firearm. There is stippling on the grip and a texture on the front trigger guard. The mag release is located on the left of the grip favoring right-handed shooters, as is the slide release. The trigger is a classic Glock with a safety blade integrated into the trigger. For an extra measure of security, there is a manual safety integrated into the frame. The sights are fixed with white dots for quick target acquisition in mind.

The magazine is a drop-free design that houses the CO2 cartridge and also the valve. It is the same size and similar weight as a fully loaded firearm magazine. The firearm mag may actually be a little heavier when loaded. The magazine holds 18 BBs and has an easy loading system to help you get back to shooting that much sooner. There is a significant advantage to a drop-free mag design with integrated CO2 and Valve. As you shoot CO2, the gas cools, and your pressure drops. The more rapidly you shoot, the faster you drop pressure. Having extra mags "ready to go" allows you to continue shooting with minimal loss in velocity and accuracy. This allows your other mag to warm up and recover for the next round of shooting.

Before you can start sending shots downrange, you need to load the mag with CO2 and BBs. When choosing CO2, we recommend Umarex High-Grade CO2. We've found them to puncture more consistently and seal more quickly to the o-ring than other brands. When loading a new CO2 cartridge, be sure to use a drop of silicone oil on the tip of the cartridge. This will help maintain your main seal and internal o-rings. You engage the CO2 by using the included Allen wrench inserted into the magazine's bottom end cap. Turn it clockwise until you feel the cartridge begin to touch the seal. With one quick motion, turn the wrench quickly clockwise. You may hear a slight "hiss" that should end immediately once fully sealed.

Loading the BBs is very straightforward. You will pull down the retention spring and lock it into the slot cut into the loading track. Add 18 BBs into the magazine and then gently release the retention spring so that it pushes up on the BBs. Like CO2, it's crucial that you only use quality BBs in your Glock. We recommend the UX Precision BBs, the Hornady BBs, or the Premium Grade Daisy BBs. Avoid BBs that flake or rust as they will foul your gun and will not yield consistent accuracy.

With a loaded mag, it's time to get to some shooting. Insert the mag into the mag well until it locks into place. With a firm grip, pull the slide back and let it fly forward. You are now "locked and loaded" for action. Take aim at your target, be sure never to shoot steel BBs at hard targets, and gently squeeze the trigger. You'll notice that the slide racks back and then forward again, just like the real firearm. This action is called "blowback." The trigger pull on the Gen 4 model is exceptional, and it's one of the areas the Gen 4 model shines above the Gen 3.

Shooting & Accuracy

While the Gen 3 was a great airgun, it suffered from a need to cycle components on the top of the mag as part of the trigger pull. This required more force from the trigger system and, with any dust or dirt in the way, additional friction. The Gen 4 model completely redesigned how the system works, resolving this issue. Where the Gen 3 had an uncomfortably heavy trigger pull, the Gen 4's trigger pull is a mere 1 pound 13 ounces. A smoother and gentler trigger pull translates into a better shooting experience and more consistent accuracy.

On a new CO2 cartridge, the shooting cycle is very snappy, with crisp feedback from the blowback. As you fire through the mag, you may feel that decrease. As the CO2 is released for each shot, it cools down, and the pressure decreases. This is where the drop-free mag design comes into play. If you have more mags ready to go, you can pull out the empty mag and insert a fresh one to keep going.

Shot count and velocity will vary based on ambient temperature and your rate of fire. Typically you should get 3 to 4 full mags per CO2. Velocity will settle down to just over 300 FPS after the first few shots, and provided you don't shoot too quickly; it should remain there until you get close to the end of the cartridge. As with the real Glock 17 firearm, when you've taken your last shot, the slide will lock back to let you know you need to swap mags. When you drop in your next mag, you simply rack the slide, and you are ready to go back to taking out targets.

We are shooting steel BBs at low velocity down a smooth barrel, so it's important to maintain realistic expectations when it comes to BB pistol accuracy. If you keep your target to 15 to 20 feet, you should get some very good groups. Ideally, you are looking to keep all your shots on an 8" pie plate, which is a good measure from a "combat grouping" perspective. The more you practice learning to control your grip and trigger pull, the better your groups will be. Fortunately, it's very affordable to shoot several thousand rounds of BBs vs. 9mm.

In our tests, the Umarex Precision Steel BBs delivered consistent accuracy throughout the useful shot curve of a CO2 cartridge. Typical groups averaged around 3.5 inches at about 15 feet. With practice, those groups would undoubtedly improve.

Summing Up

We've mentioned several times in this article about the nature of replica airguns, and this is where the Glock 17 Gen 4 BB pistol comes into its own. If you already own a Glock 17, this becomes one of the best training tools you can buy. For a fraction of the cost of ammo, you can purchase this airgun and all the CO2 and BBs you could possibly shoot. You can develop critical muscle memory practicing with your airgun, as you would training with your actual firearm. Airguns won't replace live-fire training. Using a product like the Glock 17 BB pistol will make your live-fire training that much more efficient and effective.

If you want to know more about Glock replicas, please give us a call and we will be happy to tell you all about them.