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Sidearms & Scatterguns Common Glock "problem"? Slide releases with loaded mag insertion

dang472

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  • Feb 3, 2012
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    Kingston, IL
    A buddy of mine has a Gen 3 Glock 19 that he noticed will release the open slide when inserting a loaded magazine hard. He did the normal searches and it looks like it's fairly normal. I never heard about it so I went home and slammed some mags in my Gen 3 23. It would do it as well, but I really had to hammer the mag with my hand to get it to do it. My Gen 4 19 does the same thing. It won't do it on an unloaded magazine.

    I guess if this is standard procedure, I won't worry about it. It does seem a unsafe considering it is auto-loading itself with a forceful mag change. If there are aftermarket solutions to this, I would love to know about them.
     
    I've shot lots of competition with Glocks and can't remember that ever happening and I slam mags home pretty hard during a match. I guess I've never purposely tried to make it happen though.
     
    This is normal and I wouldn't worry about it. I've had it happen with my glocks, and seen it happen with friends glocks and occasionally other pistols. Also, Ken Hackathorn covered this in a class I took with him and indicated it was normal for glocks. I'm not sure when you would do a forceful mag change and not want the slide forward quickly anyway.
     
    I have also seen this with Glocks, as well as with the M&P and various Rugers. While it may be "normal", it is not a design feature on any of them. At times, have seen the slide go forward when the mag was not fully seated, and no round was chambered. Just something to keep in the back of your mind, are you willing to bet your life in any given situation, that a round did chamber. Does give excellent practice for an immediate action drill or press check.
     
    Yeah, try changing out the slide release. That'll usually fix it. You could try bending the spring out if you suspect that, but replace it soon after. I forget what was the exact detailed cause. I think it had to do with the geometry or specs of the part, but a weak spring will also cause it, because when you slam the mag home it either dislodges the slide and/or the slide release enough to make it release. It could have to do with the width of the frame, that occurred to me, but fixing it remains the same.

    I typically use the factory slide releases with emery cloth epoxied on; I have a bunch of parts after using Glocks for a long time, so if it isn't spring related I just try different ones until I have a good one for that pistol. There's this aftermarket part, I truly don't know who makes it (Aro-tek?). It is just like a factory slide release, but twice as long and just as flat. That one works pretty well, better than the factory extended one IMO, and you can glue emery cloth to it.

    None of my Glocks do this now, but some have in the past. Hope that helps, it's a pretty cheap part at any rate and having a couple on hand isn't a bad idea.
     
    Completely normal. It seems to be more a matter of angle rather than force though. I found that there was a sweetspot on the rear of the butt, about where the hollow portion of the backstrap is, that if I hit is just right I could get the slide to release almost 100% of the time, so I used it to my advantage on my reloads. I was always prepared to manually release the slide, but WAY more often than not my reload was accomplished this way. Our Dept firearms instructors even discussed it as something that could be used if we got the technique down.
    I never saw it as unsafe because I've never inserted a loaded mag into a weapon, especially forcefully, where I DIDN'T the want the slide to go forward.
     
    I have found this happen from time to time but you have to hit the mag pretty hard. Nothing unsafe about this. As mentioned above when inserting a full mag with the slide back you will be returning the slide to battery one way or another. I don't use the slide release at all but use my weak side hand to pull back and release in all my drills. I think cfulback32 covered it in his post. Personally I would not change out a slide release based on the description....keep on whacking that Glock!
     
    I have multiple plastic guns this happens. I prefer it. I've never had it go forward and not load a round. That would be unusual. I've owned 8 different 1911's, never had this happen on any 1911.

    I prefer it on my plastic guns.
     
    It won't do it on an unloaded magazine.

    It won't do it with an empty mag because the mag follower provides spring tension on the slide stop lever. (for whatever reason, Glock calls this part a slide stop not a slide release)
    37/38/39 Ext. Slide Stop Lever : 3-Pin Ext. Slide Stop Lever, 3-Pin | Brownells

    It will do it with no mag inserted and the force applied to the bottom/magwell of the gun though. I believe it's the inertia jarring the slide stop to disengage. Like hitting the butt of an M4 with the bolt locked back.

    Take your empty Glock, with the slide locked to the rear and adjust your grip so the meaty portion of your hand extends past the magwell, no grip adjustment need (for me any way) with the smaller models, 23, 19 , 26,27. Now slam your hand on a solid surface. I used my knee/quad like I was breaking kindling. The slide will go forward.

    I think its a unintended benefit rather than a safety issue. As has already been stated you're putting a loaded mag in the gun, you want it loaded and in battery ASAP.
    I have not seen the slide releasing and failing to chamber a round as a result of seating a fresh mag. I have seen a buncha cops racking the slide and ejecting a live round due to a lack of trust in the process and a, "just to be sure" mentality though.

    I'm one of my department's firearms instructors and a Glock armorer FWIW.
     
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    Yeah, try changing out the slide release. That'll usually fix it. You could try bending the spring out if you suspect that, but replace it soon after. I forget what was the exact detailed cause. I think it had to do with the geometry or specs of the part, but a weak spring will also cause it, because when you slam the mag home it either dislodges the slide and/or the slide release enough to make it release. It could have to do with the width of the frame, that occurred to me, but fixing it remains the same.

    +1
    It is likely the spring tension on the the slide stop. As others have said, you can bend the spring out a tad and stiffen the stop up. And depending on how many rounds are through the gun, the rear of the slide stop where it contacts the slide can get rounded just a tad from all the friction with the notch in the slide. This will reduce the surface area contacting the notch in the slide. It's easy enough to take a small file and square up the rear of the slide stop if you don't want to purchase one or wait for another.
     
    This is a phenomenon that happens with plastic frames. It's all about where the application of force is applied.. in this case at the back of the magwell. It's an intertia thing that when practiced enough, will happen with some regularity.

    I wouldn't train to rely upon it, and work on your technique to avoid it.
     
    Well shit, I guess I'm the odd man out. I have a box of different parts and have never had a problem resolving this. I own about five Glocks dating from the 80's to recently. Those parts are stamped, not machined. They wear easier, the spring isn't all that strong, and they can be slightly out of spec.

    Again, get a few and try swapping them.
     
    It happens virtually all the time with almost all of my Glocks, excepting the G36.
    As to training, familiarize yourself with the weapon and its characteristics.
    If it happens all the time, train that way.

    Notice how it depends from individual to individual. That's an indicator of variable geometry and forces in and around that system. Otherwise they should all function the same.