300 BLK problems

[Fist_gonzo]

Try some 110 or 125 grain stuff. Or maybe open the gas port up a bit? Or try a non-FA carrier?

Thanks Ray, got a semi bcg from another build I'm gonna switch

Find some factory supersonic ammo and run it through first. If it still malfunctions, then we could give you more accurate advice.

Picked up some 125gr Remington premier otm from Bowers gonna see if that cycles better, I know that the other stuff was "practice ammo" was only rated at 1975fps out of a 18" barrel

He says it's a carbine length.

+1