I have shot 1 mile with a 223, 6xc, 6.5x47 and 338 Lapua. Accuracy wise they all shot reasonably well, however, splash is much easier to see with the 338 and wind changes are much less of an issue with it. A 6.5 PRC with 144, 153 or 156 should easily be able to make it to 1 mile. You will have a...