Feeding/accuracy issues - Grey Ghost Precision Match Glock 19 Threaded Pistol Barrel

I'm using it with a faxon arms slide I've only fired 250 round through it and the finish is wearing off. I get at least one failure to feed per mag. And when it does chamber ill miss a whole mag at 20 yards which doesnt happen with a oem barrel. Maybe it just doesn't work with the faxon arms slide.