IMO, the difference in these cartridges is minimal. If your going for BC then the 7mm, but what are we talking at reasonable range...a couple clicks on the scope? For either cartridge over a certain range your going to be clicking the elevation on the scope so the .277 is going to take a little more.
I have heard that people are plenty happy with the .270 130 gr Barnes TSX for dispatching animals. It seems to me that it starts getting into how much recoil do you want for that added performance?
