Sure 220's work from an '06, but to my mind they are a solution to a problem that no longer exists. Modern premium 165's - 180's drive deep, are accurate, and are utterly reliable at '06 velocities. They also leave you shooting a rifle trajectory rather than that of a howitzer. When I am hunting a new environment, the best favor that I find that I can do myself is to ensure I use a premium bullet with sufficient SD/BC that extends my point blank range far as possible. Extra-heavy for caliber bullets (i.e. 220's in .30's or 350's in the .375) do the opposite and seem to me an unnecessary anachronism with today's technology. All that said, if you have confidence in those 220's, use them.