Questions like this one simply make me cringe. We have no idea what the original poster's experience is. All we know is ".300 Ultra Mag" and "out to 700 yards" - asked on an online forum.

Though there's no question in my mind that guys like RR do this as a matter of routine, they talk in a language most average hunters don't have time or patience to learn. I'd venture a guess here that they're not parking their rifle at the end of the season and then sending a couple of sighters downrange at the beginning of the next season? Guys I know who do this kind of stuff do it almost year-round, it's their passion.

We can't tell any of that from the original post. While it's not safe to assume complete inexperience, it's not safe either to credit or grant benefit of the doubt that the original poster has sufficient experience and resources to be a credible long-range hunter, PARTICULARLY when the question is asked on a non-long-range hunting, generic by all other descriptions, online forum.

So, my recommendation would also be to seek advice on a forum more dedicated to this type of hunting. I'm probably pretty average here in terms of ability. Like many here, I'll probably cast a suspicious eye toward anyone claiming to make routine shots on big game at over 400 yards (not to say that some don't do just that). I've been tempted at times to take shots farther out than what I practice at. I've seen the big-game version of waterfowling's "sky buster" shoot at game at ranges well beyond their experience level. I've overheard conversations at the gun counter that make me wonder which magazine article brought the potential buyer there and whether they've otherwise spent any time in the field. I think most of us here have experienced some of those things.

Becoming a long-range hunter is more than which rifle and scope. I'm certain you'll find that out on a board more dedicated to it.