For long range i dont see how one could beat the performance of the .243.
Some of you dont like it for deer but it clearly is the better varmint cartridge.
Heres a 220 swift .243, 22-50 comparo.
Look at fps at muzzle then at 500 yds. look at wind drift at 500 yds and long range trajectory.
You also dont have to worry about wearing a barrell out either.