At this years shot show, Nosler announced a new cartridge, a 6.5 MM based upon the 404 Jeffery case, which is the parent case for the WSM,WSSM, and RUM, and 375 Ruger.
They are advertising Muzzle velocity of 3400 fps with a 129 grain Long range Accu-Bond. With more retained velocity& energy @400 yards than a 30.06 has at the muzzle.
When zeroed at 350 yards, it has a pint blank aim on a deer sized target from 0 to 415 yards with only 5" of drop@ 415.
I'm toying with the notion of building one.
#1, since this cartridge is about the same OAL as a 30.06, It will need to be a long action.
#2 most of the WSM are built on a large shank action
#3 were any large shank actions made on the long action platform?
#4 Can you have a standard long action opened up& re-threaded for a large shank barrel?

I'm not planning on building this month, or next, It may just be a pipe dream for now, But hey, we can have fun with that too.

http://www.26nosler.com/