Ted, I used a 75gr X on deer and boar out of a .257 Wby with very good results. Penetration and tissue damage was suprisingly extensive. As noted on another thread the velocity was chronographed in the 3975fps range. Three boar and one large Whitetail buck fell to this load. The ranges were from 100-175 yards and no bullets were recovered.
Don't bother Ted.
Because the 270 Win is quite capable of killing big game every bit as quickly as "much more powerful cartridges." :roll:
Don't bother Ted.