I have a .300 win mag w/ Leupold 4x12 scope, It is more capible than I am. I don't spend the time mastering long range shooting, I can hit milk jugs @ 500 (which is long range to me), but I've never shot an animal that far with it. I just keep the wind right and try to keep my shots under 300 yrds. I don't think any of the above calibers or optics will dissapoint, more often than not, its the person behind the gun. There are some very good tips here, have fun! My only advise is don't get too caught up in shooting farter than you need to.