I also expect smaller diameter bullets to be not quite as well balanced as larger diameter bullets. I found this to be a general tendency when fooling with a Juenke Concentricity Compatator tool years ago, and it makes sense, as a .0001 variation in diameter (or jacket thickness) is comparatively more in a smaller caliber bullet than a larger caliber.
One of the reasons Ol' Elmer gave for favoring larger bores way back when. Some things are slow to change, eh?
