Talked to CA, and they shot me over an RMA, and said they want it back to let their senior custom shop gunsmiths look it over and find out WTF is going on with it, and shoot it, and see if they can reproduce the issues I'm having. If so, they'll put a new barrel on it, shoot it and test it, and then ship it back to me once it's to their satisfaction, to ensure my satisfaction. Really nice guys at their CS department. They said they don't mind that I was shooting handloads through it, since we talked for a while, and he seemed confident I knew what I was doing. He said normally with every Joe Blow they don't really like it if they do, because you just never know, but since I did a baseline test with multiple types of factory ammo first, they have a good baseline to go off of for testing.
BUT, before I ship it off next week, I plan to try ONE LAST THING just to eliminate ALL factors... I'm going to swap on my new Burris XTR-III 5.5-30x56 SCR 2, just to ensure that nothing is wrong with the Kahles K624i... That will eliminate ALL external factors and possibilities, other than the barrel being defective. If it still shoots crazy, then it's going back to CA for a new tube and blueprinting.