Cases running not running concentric in a Lee case holder when using a drill to spin them. It seems to vary from case to case. Some run with nary a wobble and then others it's almost irritating. I suspect this has to do with case head dimensions varying a few thou from case so they will never all seat properly in the holder. I do my best to ensure the case is 'bottomed out' in the holder but nothing changes. I finally found my # 3-2 Morse taper adapter so I could run a drill chuck in my lathe (making it the biggest case trimming tool in history) and thinking now that I had the shell holder in a solid fixture it would help, especially with tightening the lock ring but I still have inconsistent case spin. OH, BTW this is happening with .223 cases.