Lets not forget there could be a new rifle involved here.
Oh, moose are like swamp elephants! You'd better go with that new .35 Whelen--your '06 might just bounce off! LOL
For the record, my great-grandfather hunted just about every animal in N. America with a 30-30 with what I might call legendary success, and moose were no exception. Unless they're breeding 'em a whole lot tougher nowadays, an '06 will do a fine job.