In my opinion, the whole theory of not releasing the slide with the slide stop is not that it will 'cause damage' but that it will wear out your slide stop prematurely. By releasing the slide with the stop you are dragging the edge of the stop across the notch in the slide. Doing this over time will no doubt wear it. Just field strip your weapon right now and look at how the stop is shined at the back edge where it catches the slide notch. This is an indicator that it is a wear point; releasing it with the stop will wear it even more in that area. Sure, it's only a 15-20 dollar part but why wear it prematurely? I'm not sure of the effects it may have on the notch in the slide; probably not much since the slide is undoubtedly much harder steel than the slide stop.
I'm new to Glock but not new to handguns. I never release the slide on any of my semi-auto pistols by pressing down on the slide stop; I always pull back on the slide to let the stop sit back down where it belongs, then release. I shouldn't have said "never" because I do it sometimes just because I like that sound and occasionally I want to make sure it's functioning properly. Of course, I would if I needed to in a real situation, e.g: in the event I had a wounded hand or was using my weak hand for something else and couldn't rack the slide.
I would rather have my strong hand gripping the gun properly and be in position to fire and use my weak hand to rack the slide. One could argue that this is an unnecessary move...(racking the slide) and that you could do it faster by just pressing down on the stop with your thumb. I disagree. If your strong hand is in position or in proper placement to fire in the way that one should be practicing over and over, I don't think it's any slower, in fact it may be faster than rotating the gun in your hand to release the slide then rotating it back again to get your hand back into position for proper grip. This was written towards the right-handed shooter. I am a lefty so it's an even better practice for me.
I think the misconception in what is causing damage is that you should never let the slide 'slam home' without a round in position to be chambered. This is something most manufacturers warn against. I don't even let the slide slam home at all if I am simply loading my weapon, instead I let it return while holding some resistance. My theory here is that I may avoid bullet setback by not letting it just slingshot forward on that same round repeatedly (over time), maybe not but I still do it that way. Now, if I am at the range and intending on shooting that round right away, I obviously don't worry about bullet setback and just let 'er fly. I am sure some military/LEOs may have a different theory; I am just going by simple mechanical common sense and what I have experienced and been told. My theory makes sense to me whether it's so or not
. Sorry I couldn't condense that but that's the way I see it.
