When building my 43 I kept having jamming & feeding problems, I ended up buying a new spring, barrel, and mags and still had the same issue. I asked a buddy of mine to see if he could help me with my problem. He seen that I had the p80 lpk and recommended I changed it out for an oem lpk I did and it started working better then ever havent had an issue since. So i would recommend getting a oem lpk.
