[tobnpr]

From a standard SAAMI chamber, I can't see how the round could ever know whether it's in a bolt gun or a semi...

Meaning, it's the rate of twist, length of the barrel and the usual "individuality" of barrel harmonics that comes into play here- with the added limitation of mag length.

Just mounted the scope on my son's "Xmas" DPMS LR-308, and when we head to the range to see what it likes to eat, the same load as his Savage bolt .308 will be on the menu (43.5 of Varget under a 175 SMK).

Varget is most always the powder of choice for the .308.