There are certain malfunctions that are human error, and others that are mechanical in nature. Just about every type of firearm malfunction can be caused by either. When we’re troubleshooting these sorts of malfunctions, we always look at it from a top-down approach.
What I mean is that we need to look at the operator, first. If the shooter (which is you) is doing everything correctly, then we move on to mechanical issues with the pistol or magazine.
We’ve found that most malfunctions are caused by shooter error in one form or another. This isn’t always the case, but shooter error must be removed as a possibility before looking at the gun. Most people want to look at the gun, first, but this is the wrong approach.
Let’s take a look with more detail, and answer the following question:
Why won’t my pistol’s slide lock open on the last round?
One of the top reasons why your slide won’t lock open on the last round is due to your thumb coming into contact with the slide stop lever during the firing cycle. The thumb will accidentally keep the slide lock lever from engaging the slide to hold it open on the last round.
There is an easy fix for this, keep reading.
How do I fix my shooting so it allows the slide to lock back:
Hopefully you’re shooting with a strong, two-handed, thumbs-forward grip. This is the best shooting grip for the control of recoil, even if it is less comfortable at first. As we’ve said in other articles, concealed carry is a lifestyle change and certain sacrifices in comfort need to be made if you’re going to be able to protect yourself properly.
This is also true of your shooting grip, or the way you hold your gun. The old ways of holding your gun, like the teacup and saucer, and some of the other ways I see people holding their gun on social media, are over.
So, assuming you’ve got a strong, two-handed, thumbs-forward grip, that looks like this …
… you simply need to move your strong-hand thumb over a bit, away from the gun, to prevent it from coming into contact with the slide stop lever.
It’s really that simple. Just sliding the thumb over so it doesn’t come into contact with the slide stop lever will solve a majority of these issues with the slide not locking back on the last round.
I talk more about this in the following video that I just recently uploaded to my YouTube channel, and try to demonstrate it:
Why it’s important for your slide to lock back on the last round:
The last thing you could ever want to have happen while you’re in a defensive situation is to have any sort of malfunction. It could throw you off if you haven’t practiced for it enough, and the slide lock malfunction is not one I see people practicing to correct.
It’s easy to correct, sure. But in the heat of the moment if you fail to correct this malfunction because you don’t recognize it, or because you don’t know what you’re doing, it could cost you precious seconds of battle time.
The best thing that could happen, is that you adjust how you shoot to prevent it from happening unless it’s a mechanical failure of some sort that you have no control over.
What about the mechanical aspect?
There are times where the slide won’t lock back due to a mechanical aspect. These times are few and far between, but it can and does happen.
It could be a magazine problem, a spring failing, or just wear on the metal parts. If you’ve narrowed it down to a mechanical failure it might be a good idea to bring your gun to a competent gunsmith to have it looked at.
Chances are good that your slide isn’t locking back on the last round because you’re hitting the slide stop lever ever so slightly. The good news is that this can be fixed if you know how and practice how to fix it.
And if it isn’t you, then maybe it is your gun. Anything mechanical will break at some point. The key is to eliminate yourself as a cause, first, and then move on to the gun — not to start with the gun.