I'm looking at a specific buying opportunity that I deem somewhat rare and it has a 9 twist barrel. As I was researching and getting all of the helpful recommendations here, I found a great disparity between Berger's Litz Twist Rate Calculator and JBM Ballistics Miller/Courtney Sg calculator. In short, the Berger calculator yielded a no go (1.27 Sg) and the JBM yielded a go (1.651 Sg) on the 140 ABLR.
If you are interested, you can click on the link I posted above or go to the Ballistics forum to read the discussion on Bullet Stability from folks a lot smarter than me to get their thoughts on these two respected online calculators. I was a bit surprised and you may be too.
When something does not make sense, or in this case two well-respected sources offer conflicting results, I look deeper.