All you can do is shoot and see, the hard part with 6.5's at that range is getting enough feed back to learn whats going on, if you can pick up feed back then you can see if it's grouping and responding to adjustments if it does your good to go. Feed back is the hardest though, as far as shooting through transonic seems like a lot of guys haven't even tried on here, either it's going to work fine or you'll scatter bullets all over the hill side for what it's worth I've shot the 140 Berger through transonic with no issues to 1890 yards but I'm playing with 6000+ elevation which helps