Glock reportedly put that little bulge on there to make sure the firing pin stays centered when striking the primer of a chambered cartridge.
This little bulge rides up against the inside part of the slide, causing the trigger bar to poke out a little more to indent the plunger a bit more. This way, Gen 4 handguns stay reliable even with their newly designed slimmer frame profile.
Unfortunately, the friction that results from that little bump grinding against and the inner parts of slide causes a rough and heavy trigger pull (which is why some people who own both Gen 3 and Gen 4 Glocks make the claim that the Gen 3’s trigger pull weight is slightly lighter) — not to mention it makes reassembly after field stripping a real pain. Also, the angle of the new connector causes it to be 5 degrees more in the plus direction, which greatly contributes to the heavier trigger pull weight.
There are some users who filed that little bulge smooth with a Dremel — they claim that filing it results in a lighter trigger pull and an easier reassembly after field stripping the gun for cleaning. The problem with this is it voids the warranty. The only way to get around the heavier trigger pull issue is by installing a minus connector to lighten the trigger pull. As for the reassembly pain, some people just get used to it.
The ejector on newer Gen 4 frames is also a little smaller and a tad bit thicker with a more pronounced curvature toward the point where it tapers, but it didn’t always look like this. Glock only installed this new ejector design in later production Gen 4 frames because the earlier ones used the same ejector that Gen 3s used which didn’t quite work out the way they thought it would — specifically, it resulted in a lot of BTFs (brass to the shooter’s face) and FTEs (failure to eject).
Newer production models now sport the new ejector after the company identified the problem with the old Gen 3 ejector being used for Gen 4 Glocks. But there’s still an issue with this. Those who weren’t fortunate enough to have bought any of the earlier production Gen 4 models have to deal with all the BTFs and FTEs these guns are known for.
The only thing these Glock Gen 4 owners can do to fix their gun is to buy and install a new part with the new ejector design integrated with it. It’s an aftermarket drop-in trigger housing upgrade kit (Part no. 30274) which in my opinion should be provided only as a free upgrade, kind of like what SIG Sauer did with the whole accidental discharge issue they had with their P320. It shouldn’t have to be put up for sale.
In a lot of cases where owners aren’t experiencing BTFs or FTEs, Gen 4 handguns would commonly have stovepipes (i.e. a kind of FTE where the spent case is not getting properly pushed out of the ejection port, causing a jam).
There are two common causes of stovepiping, the first of which applies to most any type of firearm: limp wristing. Limp wristing is where there’s not enough user resistance against the slide, making the whole gun move back instead of just the slide moving back.
This causes the slide to move back slower, which causes the case to get stuck. In most cases, proper training and more time in the range doing practice shooting helps, but with earlier production Gen 4 Glock models it’s not that simple.
The newer recoil spring assembly with dual captive springs are designed for more powerful NATO versions of common handgun calibers. The dual springs are too heavy for lighter factory loads and reloads. If the user knows that limp wristing isn’t the cause of stovepipes, they can contact Glock at (877) 745-8523 to ask about their Recoil Spring Exchange Program and request for a new set of recoil springs.
A Glock representative will ask for the handgun’s serial number to see if it qualifies for a new recoil spring and if it does, they’ll send a package that includes a new recoil spring and a packing slip to send the old one back to them.
As far as we’re aware, all of the issues surrounding earlier production Gen 4s have been resolved. For one thing, Glock wouldn’t have entered the Modular Handgun System Competition in 2016 with their Gen 4 handguns in 9mm (G17 and G19) and .40 S&W (G22 and G23) as their MHS entries if all these Gen 4 problems haven’t been fixed yet.
It’s been eight years since the earliest production Gen 4 Glocks were released, and after reading through countless forums, talking to actual Gen 4 Glock owners and testing some of them ourselves, we can say that all these issues have been resolved in newer production runs. All current production Glock Gen 4 pistols are as reliable as ever.
Now there might be a few Gen 4 pieces in your LGS that are from older production runs, but even then, all you really need to do if you recently happen to have purchased one is return the piece to them and either ask for a refund or a newer production Gen 4 Glock as a replacement. If you have a Gen 4 Glock 42, you might want to take a look at the best Glock 42 holster available.
I’m personally not a fan of Glocks and I don’t think I ever will be, but these handguns are popular for a reason: they strike a good balance between affordability and reliability. I love my EDC to death, the gunsmith-tuned Norc 1911 I mentioned earlier — but I wouldn’t feel undergunned if all I’m ever left to carry is a Gen 4 Glock.
This article by Mike Ramientas originally appeared at Gun News Daily in 2018 and is being reposted due to reader interest.