For 168's and 175's? I would think a 1:12 would be plenty, but your the chief of the .308 tribe!
Tank
Thanks Tank: But I don't consider my self the chief of the 308s . I have had lots of experience with them
and there fore have an opinion based on shooting them at matches and at long distances
for many years. (600, 800, 900,1000, 1100 and 1200 yards) and have tried all of the .308 bullets
that were available at the time and the 168s were the best all round because of velocity and BC.
The larger bullets were used only under the worst conditions at 600 yards and drop was terrible.
The go to twist rate was 1 in 10 because of the velocity of the 308. With the big magnums
a slower twist is OK. The match grade rifles with a 1 in 10 would shoot anything but the ones
with the 1 in 12 would only shoot the 168s and 180s well. anything heaver would not stabilize
well enough to shoot long range.
But don't take my word for it look at what a premium barrel maker like Lilja recommends.
Even the big 300 RUM likes the 1 in 10 with any bullet weight.
And you are right, the 1 in 12 will work in the 308 if you stay with lighter bullets but if you try
the 180 and up you may not be able to get them to shoot well, and it does not cost more to get
a 1 in 10 barrel that will handle the 160s to 175s well.
Some of the bench rest crowd use less twist but the conditions and distance are better and they
can make them work within there needs.
I am not an advocate of tight twist just the best all round twist depending on velocity, bullet
weight and distance to be used with a particular cartridge.
Sorry BH; but the 168s were the bullet of choice for the 1000 yard matches in the 308s and if
they tumbled they would not have been.
J E CUSTOM