I tend to promote less powerful rounds than Wyocoyotedude...but he's absolutely right about the 500ish yard thing, and certainly the 300 or so yard limit of the OPs.
Even with today's "modest" equipment and bullets, shooting out to 4-500 is no big trick, and requires very little high tech equipment...plus that is the distance zone where a big boomer with regular bullets may actually help a guy out with range. The really high B/C bullets don't give a guy huge advantages until you're out past that distance IME.
Cross canyon shots can fool a guy though, so I still do carry a rangefinder to make sure I am within my comfort zone..
