The crew I hunt with uses the small caliber stuff, /222 Rem, /17 Rem. ,.223 rem,
and now a .204 Ruger.
I ahve used in the past most calibers in the spectrum from 22 mag to .58ML,
FMJ's, varmint bullets, hunting bullets, match bullets , the works.
What we have found that works for us for the most part , is a small caliber varmint bullet,
(TNT, Blitzking, SX, stc.) moving at or around the 3,200 - 3,300 mark.
The Ruger and the .17 are the exception.
We hunt using a variety of calss and shoot our animals anywhere from 20 to 300 yards.
Peltdamage is kept to a minimum, and these calibers are more than accurate enough.
We found that the 22/250, .220 swift, 243 ect. were just too much for the majority of our shots.
That works for us, it may not be the best set up for everybody.
The big thing is not what you use, IMHO, but how you use it.
Get comfortable with the rifle and the ranges you plan to use it in....
Cat