I let the bushing float (more than a little bit), I let the die float (either in a Forster Co-Ax press, or w/ a floating die ring on my 550), and I use the floating carbide expander ball. *Usually* I get runout around 0.001", even sizing down Winchester .308 Win necks from .343" (fired) to .329" (sized neck before loading bullets), which is a bunch. For my Lapua stuff like 6 BR or 6 Dasher w/ a .272 no-turn neck... almost zero runout.