Totally lost, never heard of something like this

Hey guys, i am having a really strange problem. I got a new upper a while ago and it is doing something i have never heard of before. While shooting some shots seem to have a louder report and a a bit moe recoil. Ex: bang bang BANG bang BANG BANG. at first i thought it may be the ammo. I roll my own… but never made mistakes like that. The ammo runs fine through my pof, dd, and aug. Does any one have a clue what’s going on? Dirty bird upper with bcm bcg.

If you have ruled out the ammo.
I would check the gas block, make sure it’s not loose.
Also, check the rest of your gas system for loose or bad parts.