I've used a 270, 30-06, 300 Win Mag and 9.3x62. The ones hit with the 270 were just as dead and many of those were hit with old cup and core bullets. I know people that have taken them with a 243, again with cup and core bullets. I've seen a 270 harvest a bison. Hit them in a good spot with a decent bullet and mission accomplished. Either of the 300WM or 338WM are more than plenty and nothing wrong with using either or a 378 Wby if you can shoot it well:)
