I swore I wasn't gonna get involved in this conversation...
But since i have a 6.5 Creed being completed this week, I spent some time on the Berger and Hornady Ballistics calculators this morning.
There is a slight edge to the 6.5/06 but it's not much and is entirely bullet dependent....If you are shooting 140 Accubonds in both, the 270 wins for drop and drift.....At any distance. It all seems to depend which bullet you're shooting, but we aren't talking much.
OTOH compare a Berger 6.5-140 to a 270-140 AB,and the 6.5 "wins".
Compare a 140 Amax in the 6.5/06 to a 150 SST in the 270 (both started at 2900 fps),and it's mere inches between them for drop and drift clear to 1000. At 600 yards the 270 shows 68.2 inches of drop and 24.7 inches of drift; the 6.5 Amax shows 66.9" of drop and 23.4" of drift.(200 yard zero and starting velocity of 2900 fps for both).
That's all? That's lost in the noise of the grouping ability of rifle, load and shooter.
What am I missing? 
