[IllinoisGun]

I just purchased a new Gen 3 G30 SF and noticed that there seems to be a bit more "play" in the slide fit compared to my other 2 Glocks in 9MM which are pretty tight comparatively. The G30 slide seems to almost rattle a bit if shaken fairly well.

1. Is this normal considering the slide is much thicker on the .45 models than on the 9mm models?

2. Or did I just happen to get a Glock with a looser slide tolerance than the others, irrespective of the caliber variety?

3. Is this something that could cause an issue due to the fact that ALL Glock slides should be consistently tighter?

Any reference/answer would be highly appreciated.

Thank you.

[Redstate]

I have a Gen 3 G26 that has a great deal of side to side slide play at the muzzle end. It has never malfunctioned and is accurate. I had a G30 that had about the same amount of play. I have other Glocks that are very tight, relatively speaking. I have a Gen 3 G27 that is relativley tight. I placed my G26 slide on the G27 frame (did not shoot it) and it was tight. I placed the G27 slide on the G26 frame (did not shoot it) and it was loose.

[Glockrunner]

Originally Posted by IllinoisGun

I just purchased a new Gen 3 G30 SF and noticed that there seems to be a bit more "play" in the slide fit compared to my other 2 Glocks in 9MM which are pretty tight comparatively. The G30 slide seems to almost rattle a bit if shaken fairly well.

1. Is this normal considering the slide is much thicker on the .45 models than on the 9mm models?

2. Or did I just happen to get a Glock with a looser slide tolerance than the others, irrespective of the caliber variety?

3. Is this something that could cause an issue due to the fact that ALL Glock slides should be consistently tighter?

Any reference/answer would be highly appreciated.

Thank you.

Maybe you need a new recoil spring.

[Redstate]

Originally Posted by Glockrunner

Maybe you need a new recoil spring.

RSA has nothing to do with the loosness.

[Glockrunner]

Originally Posted by Redstate

I have a Gen 3 G26 that has a great deal of side to side slide play at the muzzle end. It has never malfunctioned and is accurate. I had a G30 that had about the same amount of play. I have other Glocks that are very tight, relatively speaking. I have a Gen 3 G27 that is relativley tight. I placed my G26 slide on the G27 frame (did not shoot it) and it was tight. I placed the G27 slide on the G26 frame (did not shoot it) and it was loose.

Well then why not get a micometer and figure it out.?

[Brian Lee]

The way Glocks are manufactured, it's nearly impossible to hold tight tolerances on the fit of the slide to the frame, so a lot of variation from one to the other should be expected.

They insert the metal slide guide rails into a mold and inject plastic, which then shrinks after it comes out of the mold, and there's no more machining on the slide rails after that. The distances you'd measure across the metal rails can vary because of slight differences in the plastic shrinkage, which can change from one day to the next depending on the person running the injection machine, and how consistent he was on the machine settings from day to day (and other reasons). This unpredictability in the final exact dimensions of plastic frames (but I'm talking frames with metal frame rails imbedded, and no secondary machining) is one reason why Glocks had to be designed to accommodate a large variation in the amount of looseness in many of the fits.

Certain other plastic guns, Like the Ruger LCP, do not mold the metal slide rails into the plastic (they are part of a metal assembly that snaps permanently in place AFTER the frame is molded separately) and don't rely on the shrunken plastic size to set the final dimension across the width of the rails - so slide fits on those guns can be just as consistent as it could be on an all metal gun.

[cciman]

Tighter tolerances requires more TLC, and potential for issues. Looser tolerances tends towards higher reliability

The G30SF has many complaints on this board caused by the slide fit being too "tight".

Obviously you have not complained about how it functions with a fully loaded mag.

Enjoy your luck.

[seed]

My G26 is very loose. It is also quite accurate (combat-accurate) and is one of the only guns I own that has never malfunctioned ever...not once. It is the very defintion of a reliable tool.

[Glockrunner]

Originally Posted by Brian Lee

The way Glocks are manufactured, it's nearly impossible to hold tight tolerances on the fit of the slide to the frame, so a lot of variation from one to the other should be expected.

They insert the metal slide guide rails into a mold and inject plastic, which then shrinks after it comes out of the mold, and there's no more machining on the slide rails after that. The distances you'd measure across the metal rails can vary because of slight differences in the plastic shrinkage, which can change from one day to the next depending on the person running the injection machine, and how consistent he was on the machine settings from day to day (and other reasons). This unpredictability in the final exact dimensions of plastic frames (but I'm talking frames with metal frame rails imbedded, and no secondary machining) is one reason why Glocks had to be designed to accommodate a large variation in the amount of looseness in many of the fits.

Certain other plastic guns, Like the Ruger LCP, do not mold the metal slide rails into the plastic (they are part of a metal assembly that snaps permanently in place AFTER the frame is molded separately) and don't rely on the shrunken plastic size to set the final dimension across the width of the rails - so slide fits on those guns can be just as consistent as it could be on an all metal gun.

I don't manufacture GLOCKS for a living but I am sure they a QA Div that checks the product to insure it meets accepted machining standards. So I took two of mine (new and old frames) and miced the rails and the slides.

Here is what I found on two G23's

Replacement frame from some time ago on a old slide:
From side to side frame rails (G206..) both measured: .091
Slide (CGX...) grooves: .097

Newer G23 (PDT...) Frame Slide matched
Rear rails: .090
Front rails: .094

Slide groove: .095

I think they are holding the manufactured tolerances pretty close in my experience.

I also measured a G27 DC (CSB...) for grins and giggles

Rear rails: .090
Front Rails: .0897
Slide: .097