1966 ,using 230fmj or 185jhp BUT, mainly when i use the original mag, if i use the Wilson's no problem, "I'm thinking the follower on the original may be catching in the groove and not allowing the ammo to hit the ramp at the right angle. AND they also feed fine in my other kimbers and my G30. Solution: I just don't use the factory mag that came w/ the UCDPll, and it also ensures that I'll not destroy that ramp any further.