I'm wanting to buy one rifle for hunting deer, elk, moose and bear and have decided on a ,308 calibre because there is a greater selection in rifles (especially semi~auto's and scout style hunting rifles), ammo, is easy to find and the option for cheap ammo, is there in ,308,,, I do recognize that 30~06 has a little more energy/accuracy out past 400yds, but my studies on ballistics has lead me to believe that under 400yds they are similar and the ,308 may even have a bit of an edge on the 30~06 for energy/accuracy below 300yds,,, However the 30~06 is available in heavier grain bullets 220+, and the ,308 is not, which may be an advantage for larger game (moose) at longer distances (400+yds),,,
I do not expect to be hunting here in BC beyond 300yds max, and will usually be shooting at game from under around 150yds,,, As for a lightweight rifle, the ,308 is a shorter round and lightweight scout style rifles are more often found in ,308
Hope this helps in your decision making, good luck with your choice of hunting rifle,,,