The .308 is a great choice for a hunting calibur whether it's deer or elk, or moose, it's a fantastic choice. I have shot itnsiderably over the years and found it to be a very , very good deer rifle at ranges exceeding 400+ yrds. I have shot match grade ammo in it, but do not recall all the particulars of those rounds as a friend of mine loaded them for me, i can tell you that they were 165gr bt. the other rounds that i have fired through it are a 168gr bthp match grade, and it is very deadly.
Lastly, as far as preformance at a great distance, take a look sometime at what the Army and Marine snipers are doing with them in Iraq and Afghanistan. That will tell you more about the preformance of the .308 then i can here in this forum.