Polymer 80 G19 light strikes?

P-80, Glock factory lower parts kit.
Live free armory combat 19 slide
Rocky Brass slide build kit.
Stainless guide rod, with I think a 13lb spring.

What would be the most apparent culprit?

I’m thinking it has to be the lightened recoil spring, since I’m pretty sure all other slide parts are Glock factory, other then the cheapy barrel.
I had two light strikes in the only 17 rounds that have been fired out of this piece.

Am I correct to make that assumption?
If so, what lb spring should I be looking for?
The recoil spring came from another kit at US Patriot Armory…and is way lighter then a factory Glock spring.

Is it moving out of battery as you pull the trigger? If not why would the recoil spring affect this? I would suspect the striker spring, or something in the upper being out of spec.

It actually does move a little bit, I’m not sure if it moves out of battery.
I only drew that generic conclusion, as that is the only aftermarket part, other then the slide, barrel, and frame.

First thing I would do is make sure you have a factory Glock striker assembly to install. Then I would check to make sure there is no debris in the firing pin channel from when the finish was applied. My Shadow Systems MR918 would give me light primer strikes with some Winchester ammo on it’s first range trip. I put a factory Glock striker spring in it an have never had another problem. David

That may be the answer. The Striker, and spring were part of a Rocky Brass build kit, I guess I just figured it was oem. I will start there.
Is a striker, and spring the same on a oem gen 3 G22? If not, I have to order one.

Yes, the spring is the same.

The Firing Pin will be marked. 40, but it’ll run just fine in a 9mm.