Unless you reload as a pure varmit round there is nothing better than the 22-250. If you're looking for something as a dual purpose that will shoot a heavier bullet for deer sized game then go with a 243.
I 'll have to disagree for there's thousands of marmots, p. dogs and woodchucks that would testify about a 22-250 ability (in the right hands) at 400-450 yards ,that is if they were still around.