The Sectional Density of a 140 Grain 7MM bullet is .248 that equates to a 165 grain bullet in 30 caliber now there is 25 grain difference and the recoil is just over 11% more in my recoil calculator, and that is assuming equal KE at the muzzle. Typically the KE of the 308 is going to be higher at the muzzle so I am giving the the 308 the benefit of the doubt with regard to recoil. The 7mm-08 load compared was also 230 FPS faster. The 140 grain bullet you compared is the heviest most manufactures list for the 7MM-08 and the 150 is the lightest most list for the 308 so the comparison is not exactly fair.