Looking for help with 2 built Glocks

[ClintC]

I have a G17 and G21 build. Yes poly80 builds that were done last year. I just got them to the range last weekend to shoot them. They both ran fine the first couple of mags. Then both slide started not going fully forward. I could bump the back of the slide with my thumb to fully close the slide. Then they would fire. Help is needed.

 

[Gunbuffer]

Ammo

 

[ClintC]

Ammo

It was all the same ammo. It was Winchester white box target ammo.

 

[Letfreedomring]

Check your firing pin safety plunger. Most of the kits come with the gen3 parts kit. Also check the the ejector isn't rubbing top of slide. When you get it running smoothly and start getting brass in the face or forehead, you might think about switching to a gen 4 ejector. Slight differences.
Safety plunger:

Ejector:

Also double check that your rails are 100% inline with each other by laying frame upside down on a known flat surface and on each side of the rails. If front or rear rail is slightly higher than other using fine grit self adhesive sand paper on flat surface then draw frame across paper till even and slide operates easily. Keep us updated.

 

[Buddhaman]

Had the same issue with my G43 build. Polished the plunger and took a bit off the shark fit to fix it. If it gives any more issues then an OEM recoil spring will be ordered. Lots of lots have weak springs but polishing the running parts helps.

 

[ClintC]

I will definitely polish the plungers and order gen 4 ejectors. Both p80 lowers where built with lone wolf parts kits. I was thinks of ordering heavier recoil springs.