RE: Why not 180 grain .270??
the .270 rifles of history and of today have 1:10 twist barrels and the 7 MMs have faster twists allowing them to shoot up to 175 grain bullets.
If there is an achilles heel in the .270 it's the twist rate it was given. Heavy bullets are not made for the .270 because they can't stabilize them like the faster twisted 7MMs......and there's only .007" difference.
IMO the .280 Rem and the .30-06 are both vastly superior to the .270...and that's still one very fine round for deer and antelope and sheep and goats.......and a helluva lot more.