With standard bullet weights, a .270 has about 15 foot pounds of recoil and the 30/06 has about 20. If your "ouch" tolerance for recoil is 18 ft. lbs., then the 30/06 is going to be a kicker. It seems to me that stock design, recoil pad, and gun weight is going to matter more here than caliber. A Ruger model 77 in a 30/06 kicks as hard as many .300 Winchesters. A Weatherby Fibermark in the same caliber is pretty tame.