I run 9 and was worried about it long ago when the Berger Stability Calculator was saying that wasn't enough, but on the advice of several friends who were already running this bullet in wildcats, and on the advice from friends at Bartlein Barrels, I went with 9 twist for the Berger 55 and it works great. I even shoot it down to about 2650 feet altitude, and no issues out past 1000 yards.
Here is a window from a month ago that represents a farm in Wyoming with a DA of 6714 feet in summer heat, but was really about 4000 feet. My SG was 1.41 with a fire form load at 3650 fps.
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