At the range this evening, shooting my P30SK, with 124gr HST, and I had a failure to go into battery. It was about an eighth of an inch shy, and was a little hard to open the slide to extract; I couldn't really see any issue, so I decided to put it back in the mag, mostly full, and try again, but the same thing happened and it was much harder to remove from the gun. At first, I didn't think it was going to come out, but finally got it by pushing the muzzle against the rubber mat on the table. Once I began looking harder, I was able to see the problem; it's pretty subtle, but the one with the blue x has a slightly longer case than the other one, and that was the issue. When I load fresh rounds from my stash, I always stand them up alongside each other, and verify that the OAL all match, but I have never looked at the case length in relation to the others. Lesson learned! I've probably went through about 1K of these and never ran across this, so that's not bad, I just need to be a little more careful with my screening.