I was kinda leaning twords the 6.5x284.
I`ve seen a 6mm Rem.AI with 105`s go 1044yds. so i know that a .243 can do it,i was just looking for other opinions,no wrong answers here...
This is just a "toy" for when the shooting slows down, we shoot in 960 yard wide alfalfa pivots so getting to 1000 is no big deal( as far as range goes) i`ve tossed 6mmbr and 220 swift out there from time to time,lots of misses a few hits.
Phil.