The 7mm chamberings have a lot of followers, but I believe there is something to be said for standard or common calibers.
If it's not going to be out past 500 yds, the .223 Rem will be cheaper to shoot.
If you're reaching out to 1,000 yds, you'll have to bump up to the 7mm at the very minimum.
For me, past 300 yds, you're into .308 cal territory. Past 600 yds, I'd step up again to one of the .338 cals.
That means the list would look like this:
Range < 300 yds = .223 Rem
300 yds < Range < 600 yds = .308 Win
600 yds < Range = .338 Lapua Mag
All those calibers have brass, bullets, dies, and load data readily available, and are already in common use for this purpose, so it will be easy to find people who have experience with the load you're working up.
Again, that's just my opinion, and I have been FOS once or twice before.
I skipped the .223 Rem, as anything you can do with it, you can do with a .308 Win, so I only have scoped rifles chambered in the latter two.