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In the 80's I shot the National Match Course with a Winchester factory model 70 Palma rifle. It had a heavy 26" target barrel with 1:12" twist. I used 190 grain Sierra Match Kings for the 600 yard slow fire stage and it was very accurate.
For 190's, a 1:11" twist is probably closer to optimum (up to 220 grain). For 175 grain and less I would rather have 1:12". 1:10" is a hold over from the 30-40 Krag and should just be religated to the dust bin of history unless you're shooting 200 grain bullets subsonic through a suppressor.
If bullets were absolutely perfect, over stablelizing them would cause little harm - even 1:8". Since bullets aren't perfect, the faster you spin them past what is needed to stabilize them, the more your groups will open up.
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I've been shooting and spotting for 155gr, 167gr, 168gr, 173gr, 175gr, and 178gr from 24", 20", and 16" .308s out from 800-1100yds regularly for the past 21 years.
I definitely have seen 12 twist .308s come apart into unpredictable impact beaten zones past 800yds.
With 11.25" twist and 175gr SMK, I've made 1st-round hits at 1130yds in no wind conditions.
.308s are way too slow to "over-stabilize", especially with quality bullets like SMKs, AMAXs, ELD-Ms, Scenars, or VLDs. Those companies spend a lot of time to ensure concentricity of the jackets, as well as uniformity of density in the cores.
If I wanted to beat my head against the wall some more with .308 Winchester, I would use a 1:9" twist in a shorter barrel because of the bullet I would pick, but I have zero interest in owning a .308 ever again for my uses. I'm more familiar with it than any other cartridge for shooting distance just because of time behind a scope, and will give a good shooter very high hit probability wind calls with a 175gr SMK or 178gr Hornady, but I like 6.5mm much better for wind deflection, recoil, ability to track my own shot, and trajectory.