Have you ever shot v000 yard competition???
Do you have a 1000 yard range near by to practice??
Do you handload?
If the answer to any of these is no, you might be better off just getting a really good hunting rifle and quaity scope and shooting 600 yard competition (and hunting) for a while.
The .308 would really shine for this, and ammo (or component)costs wouldn't land you in the poor house.
And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.