No way in heck a 1-9, no one is doing that in a 308 unless it is setup exclusively for 220s and subsonic and then they go straight to the 1-8 for the 240s like the Whispers etc.
Better yet, be more careful about the reamer you use. Go to the long range target shooting forum for detailed discussions on the 308 for LR and those bullets with twists and what reamer to order for the throat. There are seveal super designed reamers out now for just that range bullets. I would go with that.
I would not waste my time on the 168 also. Either go to the new 155s or the 175 and Berger 185 as all of them will make 1000 plus, where as the effective range of the 168 is 900 or so and then it goes transonic and starts to tumble and keyhole.
For 168's and 175's? I would think a 1:12 would be plenty, but your the chief of the .308 tribe!
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