Thread: Glock slide closes when slamming a mag home

Hello. On my g23 and g30 sf, when the slide is locked open and I slam a new mag in, sometimes the slide shuts into battery on its own. It does NOT do this with my g27. From what I've read on the interwebs, this seems to be somewhat common. ANyone else experience this? What are your thoughts on it? The g23 has <2k and the g30 <1k rounds, so I'm pretty sure its not from wear. I cant see how it would be unsafe. But its not really cool to train with a gun that does something funny "sometimes".

Originally Posted by CleverName

Hello. From what I've read on the interwebs, this seems to be somewhat common. ANyone else experience this? What are your thoughts on it? .

Anyone else experience it? Why yes---it's somewhat common. Glocks do it, so will some others. Don't rely on it, just accept that it's a sometimes thing. You can stop it---but it takes a deft hand with a file to cut the notch in the slide at a slight angle. If you put on a extended slide release, it will make it do it more often.

Originally Posted by CleverName

...when the slide is locked open and I slam a new mag in, sometimes the slide shuts into battery on its own...

Hey Clever - my old G22 did that. I had run 10k+ rounds through it over time and when I had a gunsmith look at it, he said the reload & failure drills were causing the slide lock to release when I was 'tapping' the mag in place. I had new mags, and when fully loaded, they needed a little extra bump... what can I say? Anyway, it's not a 'common' problem, but it's not unheard of. I am certainly not a Glock armor, but perhaps the lever can be replaced, and a new one may not have as much wear which could possibly have something to do with it? Glad to hear I'm not the only one with the problem! (I no longer have the beast, but it was a solid shooter - night sights, polished feedramp, fast & dependable). ~Bobby

It happens about 90% of the time on my Gen. 2, and Gen. 3 G17's. I used to own a Gen. 2 G21. It happened about 90% of the time there too. I always kind of look at it as a bonus.

My G23 Gen 3 will do it often. Just got my gen4 G19 and don't know about it yet. I don't mind. I'd actually like it if it did it every time.

Sometimes I've wondered if I was touching the slide release when it happened.

I agree that it's not fun to train with a gun that does this sometimes, especially if it does not ALWAYS pick up the round in the magazine and chamber it. The last thing you want to get in the habit of trusting with your life is a gun that may or may not be loaded.

Glocks are not supposed to go into battery automatically. It is not part of the design, and it's not what happens when most people run them, so two likely possibilities exist in such a scenario:

1- Your hands are large enough, or your hand position is such that your right thumb is riding on top of or touching the slide stop lever when you shove the new magazine into place. This problem can be exaggerated if you are using either a Glock factory extended slide stop, or worse, an after market extended slide stop. Either way, it should be easy to isolate this as a problem: while performing a reload, make certain to keep your thumb up in the air, well away from the slide stop while doing everything else the same- within several repetitions, you'll know if this is the culprit.

2- If you have frequently used the slide stop as a slide release, it can wear to the point where it gets a little bit more "sensitive". If you know how to remove your slide, look at the upper rear of the slide stop. The engagement surface should be nice and square. If it is not, consider replacing it with a new part- they are inexpensive and available all over the place online.

If neither of these things helps you find your culprit, you may consider seating the new magazine less forcefully, or playing with the direction you insert the magazine (straight up, palm at the back of the mag base plate, palm at the front of the base plate, etc).

Hope this helps. If it doesn't, feel free to hit this thread with more info, and I'll try to troubleshoot it as best as I can.

BGRF

It's a non-issue. Many pistols do it.

Thanks for the responses guys. Other than steel sights, NY-1 triggers and 3.5 connectors, my pistols are stock. I looked at the slide stops and other than some paint wear, theyre in good shape. The only time I really need to whack the mag is when the slide is closed, so I think I'll just except it for what it is and during reloads not seat the mags so forcefully.

I have a HK P2000, Bersa .380 and XDM that all do it. It's just a matter of physics. I wouldn't rely on it for self defense but I guess I slam mags home pretty good because it happens 95% of the time target shooting

Its common on glocks if you SLAM the mags. Don't train/plan on that happening, but not a problem either.

I know of guys who leave one cartridge out of the mag because if the mag is full it's harder to seat. That's not only true of Glocks.

I still "think" that when mine does it, my hand is covering the slide release, but Grommit is right. If you hit it hard enough, the physics of imparting kinetic energy to the gun while the release retains its inertia could easily release it - simple physics.

Physics are such a cruel task master... Just like hitting a hammer on the handle to drive the head back on... Inertia is the root cause of the issue. There may me some other mitigating circumstances such as a worn or mis-machined slide release that isn't fully engaging the notch in the slide. As said above it can be fixed both through mechanical means and training... Its Tap,Rack,Bang.. not SLAM, rack, bang...

I'd normal.

My HK P30L does it, if I slam it hard.

It's normal, my g19 and g23 did it too.

I'll just except it for what it is and during reloads not seat the mags so forcefully.

I wouldn't seat the mags less forcefully because of it. It eliminates a step (rack) in the reloading procedure. It's better to have the thing go into battery as soon as the mag is seated rather than risk having the mag fall out because it wasn't seated hard enough, which would be annoying in training and potentially deadly if your life depended on it.

I've some Glocks that do it and some that dont. This has also been my exprience with my Heckler and Kocks, my Sigs, Smith and Wessons, and Springfields. It can happen with any gun manufacturer. Its not a defect or a problem though. Just a variable that can happen to anyone at anytime.

However, when this happens, there is no guarantee that it will chamber a round. This is why I've always been trained to rack the slide after a reload anyways. Muscle memory etc. Worst case scenario is that a bullet ends up on the ground. Best case is that your gun fires when you need it to and your life is preserved.

When I went to Glock Armorers School, they described it as a design feature and it should do it every time. The slamming (and you have to do it like you mean it) created inertia moving the slide to the rear and allows the slide stop to disengage. Just went to my Armorers Manual and the info is in there (c.1996)

Originally Posted by TacticalOptions

When I went to Glock Armorers School, they described it as a design feature and it should do it every time. The slamming (and you have to do it like you mean it) created inertia moving the slide to the rear and allows the slide stop to disengage. Just went to my Armorers Manual and the info is in there (c.1996)

Got to love Glock, kings of taking "issues" and making into great advancements and new "features"!!!! When you've attained perfection, why not change it every couple of years.

Originally Posted by TacticalOptions

Just went to my Armorers Manual and the info is in there (c.1996)

Well darn it I sure wish I could find it. It's not in my 1992, 2002, or 2009 armorers manuals. Does anybody have a page number?

Originally Posted by ogre

Well darn it I sure wish I could find it. It's not in my 1992, 2002, or 2009 armorers manuals. Does anybody have a page number?

I didn't think Glock made it a feature yet.... but still looking forward to coming through with proof!

Fwiw My G23 series 3 and G19 Series 4 will both do it every time, with a sharp rap. Not betting my life on it though. Stay ready to hit the release, and I practice gentle mag inserts followed by slide release.