James B in Post # 12 you said you needed to compare bullets of equal sectional density to give them all a fair shake. Comparing cartridges this way is not a fair shake comparison. See the results below for a 3000 FPS impact:

Caliber WT SD KE lbs/Momentum

270133 .248 2658 57
7MM 140 .248 2798 60
.308 165 .248 3297 70.7

When you compare bullets of different calibers with equal sectional density and equal velocity you will see the larger bullets have far greater terminal performance. As demostrated above the .308 caliber bullet has 639 LBS, 24% more kinectic energy and 24% more momentum than the 270. Hardly a "fair shake" comparison.