Mencius wrote:
Flintknapper - You said up to 400 yards is not really long range for a 308 on deer-size animals. What would you consider the upper limits or long range for this combination (heavy barrel M77, vx-III 14x scope, .308)?
Well...
between 300-400 is not. There are factory rounds (Hornady Light Magnum) that would take you (ballistically) to 500 yds and a bit beyond with a 150 gr. bullet. I'm talking about having approximately 1,000 lb. ft. of energy still available.
The point being...the .308 is capable of cleanly taking deer well beyond 300 yds. and even 400 yds.
The limiting factor is how accurate any given load is out of YOUR rifle and your ability to make a good shot. IF you have a rifle capable of "Minute of Angle" accuracy (1" @ 100 yds.), then at 400-500 yds. we talking about 4"-5" groups under ideal conditions.
So...while the rifle/bullet combination might be accurate, when under "field conditions" (less than steady rest, crosswind,
exact yardage unknown, etc), you still might need to "pass" on certain shots.
This is easily understandable when you consider the rifle is probably only capable of a 4" group at 400 yds. (the mechanical factor), then we add in the "human factor" (breathing, trigger control, flinching, etc) and thats probably good for another 1"-2" for most folks, so right there...you're likely to be off 5"-6" from point of aim BEFORE the influence of wind and range estimation (range can negated with a range finder).
Anyway, to answer your question: The cartridge (in common barrel lengths/22"-24") should give you a practical outer limit of about 500 yds.
Under perfect conditions...I would take that shot on large deer (Mulies or large Whitetail), but would pass on small deer (Coues, Texas hill country, etc). Much smaller targets.