I think between the two subject cartridges the specifics of the rifle and scope have exponentially more effect on determining accuracy than the caliber.
Have a Savage 116 in 30-06 Sprng and a Savage 10 in 308 Win.
Both with Accutrigger and Accustock.
They both print 5-shot ragged holes @ 100 yards with the 165 grain Nosler Accubond bullet.
If you looked at the groups you couldn't tell whether it was a 2-hole group or a 5-hole group @ 100 yards.
The 30-06 sports an Elite 4200 Bushnell 2.5-10x40mm scope and the other a Leupold VXII 3-9x40mm scope.
They'll both shave the pubic hairs off a house fly and leave the intact nuts swinging in the shock wave.
