What vel do you run your 168SMKs?
For 155Scenar, most agree that they perform the best just over 2900fps.
How about for 168SMKs? What velocity are your rounds? According to 6mmBR's 308WIN page, they are looking like 2600fps-ish..... is that the "sweet spot"? In your experience?
Personally I use 42gr RL15 for 168SMK, they do pretty well, I am trying to see if I want to explore to increase the powder a little bit since for extreme ranges, the drop is quite a bit more than the 155Scenars.