Not really sure why you would want to shoot the 220's in a .30-06? When my day gave me his .30-06 many years ago, he gave me some leftover rounds that he had, and some were 220 grainers. My father and mother were missionaries in Somalia in their earlier years, and these 220's were purely to be used as close range stopper rounds, not really for normal hunting. I definately think you would be much happier with the 180's. People trying to do what you seem to want to do with your .30-06 end up turning them into .35 Whelens/.338-06's to shoot the heavier bullets slower. Good Luck.