Hi. I am building a 6.5 on a 300 Win Mag action and am not sure if I should go with a 6.5 Rem Mag or a 264 Win Mag? I am using a 26" shillen 1 in 8 twist and want to shoot 140 VLD's. It looks like the 6.5 Rem MAg may be the way to go to get 3000 fps and almost 99% case capacity vs around 75% case capacity of the 264 Win Mag. Please give me the good and bad of each? P.S. would like to get around 1500 or more shots out of this barrel.