Re: Another Which Cal ????
Either the 270 or the 308.
Of course I would lean towards the 308 but I am biased there.
As a side point, running 190 Berger VLD's, You will have more energy at 800 yards than the 270 running 150's (about 100 pounds). The difference in windage is between 3 and 4" at 10 MPH to the 270's favor.
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.