After studying up on the .256 Newton I decided to build a 6.5-'06, that was about 1980. It is still shooting well from its #3 Shilen barrel that I cut to 600 mm (23.6") and mounted on a Rem M700 action. Starting that project today I would go with something short and wide, oh wait that would be the 6.5 PRC I decided to build.
jim