Slide will not lock back with some mags

[stormdragon]

Here are the facts: :D

I have two Delta Elites, one stainless, one blue. I bought two Colt mags OEMed by Mec-Gar, and have two stainless mags, both specifically Colt Delta Mags which are not Mec-Gar. All the mags have rounded followers. I have one additional Mec-Gar brand mag that has a stepped follower. When taking down the blue Delta, the slide release is difficult to remove. It is more difficult than removing the slide release on the stainless.

Here is the problem: :mad:

With the Colt OEMed mags the slide on the blue Delta will not lock back either manually with the mag empty or while shooting after the last round. With the stainless mags, the blue Delta WILL lock back both manually and while shooting. With the Mec-Gar mag with the stepped follower the blue Delta will lock back.

The stainless Delt will lock back with any of the mags both manually and when shooting.

Whether racking the slide on the blue Delta there is a bit of a hitch as it moves forward. However, the gun works just fine with the stainless mags or the Mec-Gar brand mag.

Question: :confused:

What might be the problem? Can anyone explain to me how the slide release is engaged when the mag is either empty or when shooting on the last round?

stormdragon

[brickeyee]

The magazine follower engages the slide stop and pushes It upwards. When the slide returns forward on the empty magazine the slide stop catches in the notch in the slide.
You can see what is going on if you cycle the slide slowly by hand with an empty magazine in place. The follower may not be catching due to problems wIth the follower, or problems with the slide stop. A slide stop that is to tight may also prevent the magazine spring from pushing it into the notch in the slide.

[Prezzz]

What he said.......

And to add to that.....chances are on the mag that won't lock the slide back, it will stick in the mag well and be more difficult to get out than the others. If this is the case, then that means the follower has jumped over the slide release and is hanging up on it when trying to remove.

[stormdragon]

I believe the offending magazines are more difficult to remove.

Why would they work on one Delta though and not the other if the problem is with the magazines? Although it is pretty obvious one gun has a problem with the magazines and the other doesn't.

It seems it's a combination of something with the magazines and something with the slide stop on the gun. Is it possible the slide stop is just difficult to more, or perhaps the part of the stop the magazina pushes is shorter than the slide stop in the stainless?

I'll have to take them both down tonight and check how they measure up. I could just change mags and be done with it, but I want to know why. Also when a rack the slide manually there is a bit of a "hitch" as it moves forward. That may be a different issue and have nothing to do with this issue.

stormdragon

[Prezzz]

Yes indeed. That's entirely possible. Could be a combination of moderate wear on both, and when used together, you get failure.

[stormdragon]

I ordered a new slide stop from e-gunparts.com.

I replaced the existing slide stop on the blued Delta and I thought it had fixed the problem, but no luck. It still does the same thing.

It appears on investigation that the follower on the offending mags either does not fully engage the slide stop or does and then moves past it and into the chamber. It's as though the follower is pushing past the stop without pushing it up. Since this happens before the slide is racked I think it's either the magazine follower or the slide stop doesn't extend far enough into the mag well. Why the new slide stop doesn't work is a mystery.

On observation the rounded follower on the Colt OEM Mec-Gar magazines is shaped slightly differently than the follower on the non-MecGar OEMed stainless Colt Mags.

I replaced the spring in the original mag that came with the gun which is a blued Colt (non-Mecgar OEM mag) with a high power spring and it still doesn't work even though the follower seems the same as the stainless mags. I'm ready to conclude that the old mag is just worn out and out of shape and that the Mec-Gar mag followers are just not right for this gun. The only wrinkle is that the Mec-Gar mags work in the stainless gun.

My next step is to take the slide stop from the stainless Delta and try it in the blued Delta and see if it works. I suppose it's possible that even the new slide stop isn't quite right.

On the other hand the gun works just fine with the original slide stop and either the stainless Colt mags with rounded followers or either Mec-Gar or Shooting Star mags with stepped followers.

I may just shug my shoulders and use the stepped mags and forget it.

stormdragon