I ordered 2 of the above spring and follower kits from Wilson Combat. I used them in the Kimber brand mags that fit the Ultra II. I noticed that while I did not get any FTF or jamming problems like I had with the Kimber springs and followers, now I get a FTRTB, or the slide not chambering the first round when the slide is released. Could it be that there is too much tension on the spring with a full 7 rounds in the mag? In other words, is the spring too long in this kit for the compact 7 round mags and is putting too much pressure on the first round to be chambered? I don't have this problem with only 6 rounds in the mag. And YES, they are 7 round mags.
Jess
Jess