RE: Ammo for .308??
I've had incredible accuracy just from the regular Federal 150 gr. nosler, Federal Gold Medal Match 168 gr.and the Federal High Energy 180 gr. Nosler.
But that may just be my gun. It seems to shoot sub 1/2 MOA with just about anything but military surplus. I can't tell you what your gun will like best but I can point you toward the front runners.
The front runners in terms of performance are the Hornady Light Magnum SST series. They haul ass at 3000 fps and are probably the flattest shooters.
Federal has several good loads. My particular favorite being the Federal High Energy 180 gr. Nosler. Other top choices would be the Federal 180 gr. Barnes MRX.
It all depends on whether you want velocity or retained energy. They all shoot about the same in terms of bullet drop. They are all pretty close on velocity and retained energy also, that is except for the Hornady SST, they are in a class by themselves.
I don't know about the Remington and Winchester offerings but I doubt they come close to the Hornady or the Federal High Energy.