RE: The new 308.
If a deer is 500 yards away, you will most likely have time to get an improvised support or get you rifle on the bipod.
I personally will not shoot a deer at over 400 yards, a whitetail deer with a 308. A mule deer or Axis I think I would limit to 400 yards and that is with a 300 RUM or Win mag.
It is easy to loose a deer when shooting at long distance if it runs very far and / or is close to thick cover.
If I where going to purpously shoot a long range shot at a deer, I would set up in a big open area that the target would be far from thick cover. I would be in the prone on my bipod.
BTW,
I practice shooting improvised positions, sitting and kneeling at 300 - 500 yards often. 300 tards is pretty simple to hit a 8" gong from sitting and kneeling. from the bipod, it is almost boring 400 yards.
But, then again we compete often at the Sniper comps and have all kinds of unknown distance long shots from diggerent positions.
FWIW
Celt