Since your starting your build you might consider the 6.5 of off the 7mm RSAUM as your cartridge.. I haven't seen a 6.5 WSM on the range, but I did shot with a fellow who sported a 6.5 RSAUM... {1k shooting} an it was very impressive. It would seem like the RSAUM might have a little better neck, for necking down, as well as holding the bullet. In either case {both cartridges being close to ballistic twines along with the {6.5 Remington Magnum one of my all time favorites} it should be a smoking cartridge. As a side note; at full throttle they are a little mean to the barrels, as a match rifle.
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