I had time to revisit my mod 10 stagger feed 223AI, played with the mag lips, bent them out maybe .010" per side and put a very small flare at the chamber end of the lip, feeds almost 100% now with 50g-55g tipped bullets and Speer 50 TNT's. Did nothing to the action feed ramp or chamber, didn't even bother to remove the mag box. I love the stagger feeds for varminting.