[JParkerG19]

Hi everyone! This is my first post, so apologize if I'm a bit of a noob. Thank you in advance for your time!

So I recently assembled a Gen3 G19 using a Polymer 80 lower and a LFA upper. Gun looks great, cycles great, feels great, but there's one small issue I can't seem to figure out.

Whenever I cycle the slide on a loaded magazine, the magazine releases. At first, I assumed I was making a mistake and accidently hitting the mag release when I changed my grip to cycle the slide. However, upon further inspection I realized that this was happening even when my hand was nowhere near the mag realease. I thought it might have to do with the fully stacked magazine and it seems like it does. It only seems to do it consistently on the first two rounds in a fully stacked clip.

I am thinking the slide is pushing down on the full magazine and, since it's full, it's putting extra pressure on the mag catch. For whatever reason, the mag catch isn't strong enough to hold against this additional pressure. Once a few rounds are out of the weapon it doesn't seem to happen as frequently, but I won't conclusively say it never does.

The mag catch on these polymer 80 lowers seem kind of squishy idk. It's my first Glock. I had a 1911 prior but that's a completely different animal. I read a post on another forum from someone with a similar problem, and the lone response said it probably needs a new mag catch pin/spring. However, I wanted to get a second opinion before doing surgery.

What do you folks think? Is this a mag catch issue? Do I need a new spring or is there more too it? Any feedback would be greatly appreciated. Thanks very much for your time, and have a great day.


Best,
JP

 

[indivi]

Welcome to the forum.

First, make sure the magazine notch has no damage, also make sure the magazine catch isn't damaged or worn. Probably also a good idea to just use an OEM Glock magazine catch. Also make sure the catch is fully seating in the notch when you insert the magazine.

The depressor ridge on the bottom of the slide pushes against rounds in the magazine when the slide is worked back, putting downward pressure on the magazine. A fully loaded mag will be under the most tension on the catch so this explains why it occurs only when fully loaded or nearly so.

 

[JParkerG19]

Welcome to the forum.

First, make sure the magazine notch has no damage, also make sure the magazine catch isn't damaged or worn. Probably also a good idea to just use an OEM Glock magazine catch. Also make sure the catch is fully seating in the notch when you insert the magazine.

The depressor ridge on the bottom of the slide pushes against rounds in the magazine when the slide is worked back, putting downward pressure on the magazine. A fully loaded mag will be under the most tension on the catch so this explains why it occurs only when fully loaded or nearly so.

Thank you for answering with such a detailed response. Yes, I had figured it had something to do with increased downward pressure on the fully loaded magazine. I didn’t think of purchasing an OEM catch that’s actually a great idea. Thank you.

Interestingly, since I wrote the post, I have tried it with a magazine loaded with FMJ and it doesn’t seem to be having the problem. The other rounds were SJHP. Idk if that has anything to do with it, but it was interesting. Maybe the shape of the rounds putting additional pressure on the mag catch? No idea. But thank you the OEM mag catch was a great tip. Appreciate you boss! Thanks again.