.243 with a good bullet will be just fine. I echo above...partition, Accubond, Sierra game king...all would be good options.
I've personally seen a handful of Mule Deer shot out to just over 300 yards with a 22-250 and 60 grain Partitions...they didn't go far.
I've personally seen a handful of Mule Deer shot out to just over 300 yards with a 22-250 and 60 grain Partitions...they didn't go far.