I need input on 1911 build

[gulfwarvet]

I have been working on an Essex ss frame and a friend of mine had a kimber slide.
He wanted to see if it would fit on the frame and it did. I wanted to check if it would feed properly, so I put his mag in the gun and found that the mag was loose in the frame and wouldn't feed the rounds unless I pushed the mag up into the well and kept pressure on it.
I am using all new parts in this build. Is there a problem with the mag catch? or do I need to try a different mag?
Thanks for any assistance you can offer

[Hawkmoon]

This could be the result of what 1911Tuner refers to as "tolerance stacking," or it could be that the hole for the mag release is not correctly located in the frame. First step (because it's easiest) would certainly be to try a couple of other magazines. If that doesn't work, try installing a different magazine release.

If neither of those works, it's time to get another 1911 that works with those same magazines, dig out the calipers, and start taking measurements.

[T-TAC]

I just finished a Essex build and had a similiar problem with a Nowlin mag catch.
I switched it with a Wilson Combat extended and that fixed the problem.