Fixed!

[Dokbrick]

Issue fixed, thank you!

[_TomT_]

What are the symptoms? What were the bullet doing when you had these FTF? Was it stovepiping or was it recessed in the mag and unable fully seat onto the feed ramps?

[ElDub1950]

I'd start by trying different ammo. I haven't run Win. Rangers through mine but some HPs don't work well.

[Carcassonne]

Is it oiled?

You might need a new magazine spring. You could also stretch the old one, but that makes it a little weaker and may not last as long, but it is cheaper than buying a new spring.




.

[Dokbrick]

fixed

[stevie]

Have you only used the Winchester subsonics? Try another brand of standard velocity ammo and see what happens.

[_TomT_]

The gun has light oil on the rails. As to the ftfs issue: it was mix of feeding up at a bad angle and also not going completely into battery. It looked as if the round was beginning the feeding process into the chamber but was halted. I have noticed on on the barrel where the feed ramp leads to the chamber that there is a slight crease in the metal (maybe not completely smoothed by the factory?) I'm wondering if the rounds are getting hung up on that. Is the feed ramp to chamber supposed to be completely seemless? (I dont remember how my other glock barrels were).

Hopefully this adds more insight.

This sounds like a magazine issue, namely the follower. Are both magazine clean? Try playing around with the springs and follower pushing them in and letting them recoil. Some times the follower could get stuck at the mouth of the magazine.

[psango]

You might try changing one of the magazine spring, I had some feeding problems
with mine and went to the Wolf extra power spring, solved the problem.

[jdg30]

It's probably the subsonic ammo. The only times I've ever had FTF's in one of my Glocks was when I reloaded ammo on the lighter side. When the gun malfunctioned I loaded the rounds at a higher charge and the gun worked perfectly thereafter. I would get regular ammo and forget the subsonic. Just use ear plugs or muffs and I'm sure the gun will function as intended.

With light loaded rounds the gun would fire then fail to load the next round from the magazine. I would have to manually rack the slide again. The problem would happen randomly until I loaded hotter rounds. I'm sure your problem is not the gun since it happens with both magazines. Subsonic ammo is a lighter charge and is most likely not strong enough to cycle the gun properly. I'd bet that standard ammo will make the gun function perfect. Try it before replacing parts on the gun like others have recommended.