A mate of mine built a rifle for a 1000yd crow. The cartridge is a wildcat 6.5x68 with the shoulders blown out & forwards to become straighter-sided and...erm... bigger. Had one in my grubby mits earlier - it's a beast! Dunno what velocities he's getting, but the parent cartridge already could do >3200fps in the 1940s, so this bugger's shooting fricking laser beams. Apparently the case is good for >72000psi! Beats the kak out of 6.5x284 in any case. Mate's client got the crow, by the way!