Are you talking targets only? As others have mentioned, targets and hunting are 2 different beasts. I guess if you find 2 bullets with near identical BC's and configurations, some load testing will tell you if they hit close to the same point at extended ranges. 1,000 yards is awful far for hunting with a 308, though, unless you're after small to medium critters like 'yotes. I'd like to try my 308 on bears out to about 600 yards, but I'm still at least one season away from being able to do that.
Damn, I'd love to have a dipper come out and show me how to shoot at those ranges, because from what they seem to say, simply owning a "sniper" rifle guarantees 12-mile kills.