I own a kimber ultra elite and a colt officer ltwt. Had the same failure to feed with both, and since I'm not limp wristed, I suspected the mags. The Colt factory 6 rnd mags seem to be the problem. After changing to the Chip McC 7rnd mags the problems were considerably reduced. Going to TEHP ammo has eliminated the problem all together in the Kimber. Next, we will look at the springs and try the wilson mags. I don't like depending on one type of ammo only.