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.308 win is a great round that can be shot quite comfortably most of the day from a heavy (10lb and up) gun. My .308 will let me shoot center crosshairs out ot almost exactly 1100 yards. Keep in mind that I have $200 custom tapered base and integral rings that gives me more useable adjustment out of my scope but keeping the ability to 0 at 100 yards. Without this base I was topping out at about 850 (if I remember right).
I would not shoot at a deer at 1100yds but I would a coyote because of the energy loss at this range. If you are shooting paper or steel, the .308 win is a real fun gun as far as you want to push it.
My gun is factory stock, action and barrel. Oh, trigger group too. I have a bead blast matte finish on the bbl and action, a custom scope base and a scope that I bought new cheaper than most people can buy it used. I had my action glass bedded by a fair gunsmith and all the other nuances were done by me so they were free.
Gun $550
Scope $475
Base $200+
Bead blast and re-blue $50
Glass bedding $50
Estimated total $1325 + hours of tweaking and tuning.