If you can find some 105 Hornady HPBT's then give them a shot in your 243 Soup. They will usually work fine in a 10 twist 243, at sea level as well.
22-250 with a 14 twist is pretty limited. The 52 grain ELD is fairly slick and should stabilize in the 22-250. Hard to get too much more out of them, but it'll get out there decently well.
Good luck!
