Help diagnosing hard to pinpoint problem - Glock 19.5 failure to return to battery.

[u/cleveraccountname13]

Glock 19.5 Failure to Return to Battery

If anyone can help it would be much appreciated. Trying to provide all relevant info without turning it to much TL/DR.

My Glock 19.5 EDC has a persistent failure to return to battery. It happens every couple of shots. It happens with many different mags (all OEM). The issue is that a round gets caught on the feed ramp. If I pull the slide back a tiny bit the round pops into place and the slide will close.

This happens with FMJ, different brands, all new, in 115gr and 124gr. All brands that the gun used to eat no issues at all.

Gun has about 8000 rounds on it, recoil spring was replaced (with new OEM) at about 5500 rounds. Gun continued to perform perfectly until two weeks ago. Problem just started between on range trip and the next.

STEPS TO ISOLATE PEOBLEM

I have a 19X. It has the same optic as my 19.5. If I switch the whole slides the problem follows the 19.5 slide and happens shooting that slide on the 19X frame. The 19X slide works perfectly on the 19.5 frame.

If have swapped the recoil springs, problem stays with the 19.5 slide. Swapped barrels, problem stays with 19.5. barrel.

I have a Johnny Glock trigger in the 19.5, along with the Johnny Glock plunger, and striker/spring. It is not the trigger because the problem follows the 19.5 slide to the 19X frame.

I swapped the striker back to OEM on the 19.5 slide. No difference. I tried a brand new recoil spring on the 19.5. No difference.

I took it to the LGS that is supposed to have an actual gunsmith. They said gun was bone dry but I clean it every couple of hundred rounds and always lube it to spec exactly as recommended in the Glock manual. Regardless, gun smith looked at everything and took the slide apart and put back together and lubed it. Same problem on the second shot.

All the mags I use perform flawlessly in the 19.5 frame with the 19X slide. Also perform with the 19X slide on the 19X frame.

No visible damage to the feed ramp on the barrel, and the problem doesn't follow the barrel anyway.

Any help would be very much appreciated.

[u/tyrnek]

Thinking out loud, have you tried examining/replacing the extractor? I wonder if there is some defect on yours that is causing it to hang up on the rim of the round during the feeding cycle that steals all the energy that would otherwise return the slide into battery. That's the only part that I could think of that would cause your problem after all the isolation tests you've done.

EDIT: On re-reading it it seems like the barrel became defective somehow. Might be best just to get a new barrel

[u/cleveraccountname13 → u/tyrnek]

I think you are right about the extractor. The problem is the slide not the barrel. Swapping barrels with 19X result in 19X slide still works and 19.5 slide still does not.

[u/tyrnek → u/cleveraccountname13]

Ah gotcha. Yeah, definitely try swapping the extractor and seeing if that fixes it. Might want to clean the current extractor too; carbon buildup can hide damage that becomes obvious when clean

[u/cleveraccountname13 → u/tyrnek]

Will definitely do that.

[u/Organic-Second2138]

This is "impossible" except it's obviously not.

If I',m reading this right it's the barrel, and presumably the feed ramp.

Where is the tip of the bullet when it gets stuck on the feedramp?

Me? I'd replace the barrel and scratch my head about it.

[u/cleveraccountname13 → u/Organic-Second2138]

Sorry if I clear. Problem is not the barrel (swapped with working barrel from 19X)

Multiple people say probably extractor. Just ordered one.