I have a 9 twist on my .270 Win but don't require it. I think the .270 Win is best served by using 140's at just over 3000 fps so as to get a very good short to medium range trajectory using 140's with a bc over .5 such as the 140 TGK and 140 Berger Classic Hunter, they only require a 10 twist. The only hunting bullet I can think of that requires a 9 twist in the .270 Win is the 150 LR Accubond. To drive it at over 3000 fps in the .270 Win you need Reloder 26 which doesn't do well when temperatures get very hot. However in a bigger case such as a .270-7mm PRC I would consider using the 150 LR Accubond (if it shot as accurately as the Bergers or TGK's) and use a 9 twist or faster.
