My buddy is a die-hard varmint hunter and with his custom heavy barrel .243 and handloads he wont hesitate to shoot at a yote from 1-600 yards. The first time he told me i just laughed at him but he sure proved me wrong.
Im not a big varmint hunter but i just use my 30-06. Its great because it gives me excellent practice so when i go for deer and elk I can be confident in making shots anywhere from 50-250 yards