ny32182
Member
If you haven't cleaned the inside of the mag tubes in thousands of rounds I would do that anyway. There are a limited number of things that could be causing this and you can easily eliminate them one by one.
-Pull the springs and followers out of the mags, wipe crud out of the inside of the tubes and off the sides of the followers. This will make sure your follower is moving freely; and it needs to do so to consistently lock open when shooting. It doesn't have to move as fast to lock open when manually retracting the slide as it does when shooting since the slide velocities are very different in those two situations. I don't think you've entirely eliminated this as a possible cause before cleaning the mags.
-Crud could be obstructing movement of the slide catch. Easy enough to see if it is moving freely with the slide off. Take the slide off, move it with your finger; pop in an empty mag and make sure it is moving... etc.
-Ammo: if nothing above works, change it for ****s and giggles. This probably isn't it, but can't come off the list until you've proven it is fine.
-Grip: The most common cause of both failures to lock open and slides locking open with rounds left in the mag. I've seen plenty of both. Shoot it left handed, let your buddy shoot it... etc. Even if you don't think your thumb is riding the catch to keep it down, it may not be obvious while actually firing.
-Worn slide catch lever? The most I've got on one is about 4k rounds; I don't know if the end that engages the notch in the slide can become worn to the point where it doesn't catch well, so that is just speculation; I would replace that part and the spring if all else really failed.
-Pull the springs and followers out of the mags, wipe crud out of the inside of the tubes and off the sides of the followers. This will make sure your follower is moving freely; and it needs to do so to consistently lock open when shooting. It doesn't have to move as fast to lock open when manually retracting the slide as it does when shooting since the slide velocities are very different in those two situations. I don't think you've entirely eliminated this as a possible cause before cleaning the mags.
-Crud could be obstructing movement of the slide catch. Easy enough to see if it is moving freely with the slide off. Take the slide off, move it with your finger; pop in an empty mag and make sure it is moving... etc.
-Ammo: if nothing above works, change it for ****s and giggles. This probably isn't it, but can't come off the list until you've proven it is fine.
-Grip: The most common cause of both failures to lock open and slides locking open with rounds left in the mag. I've seen plenty of both. Shoot it left handed, let your buddy shoot it... etc. Even if you don't think your thumb is riding the catch to keep it down, it may not be obvious while actually firing.
-Worn slide catch lever? The most I've got on one is about 4k rounds; I don't know if the end that engages the notch in the slide can become worn to the point where it doesn't catch well, so that is just speculation; I would replace that part and the spring if all else really failed.