Suggestion: Try adjusting your ballistics solution to 2535 FPS and G1 BC to .500. BC is dependent on a velocity band and you are shooting around 2500 FPS MV near sea level or approximately an adjusted air density standard equivilent to 900 ft elevation. I'm puzzled by your 500 MOA correction, not matching up to a ballistics profile. Also, what is your ES? A 40 FPS ES will create approximately a 1 MOA difference at 800 yards. Also what is your precision at a 200 yard zero in MOA?
Try the suggestion and see what results you achieve and measure your ES and precision MOA.
MMERS- I was thinking, perhaps I am wrong, he was shooting groups to establish a drop confirmation. IF that is true can you rule out ES? I ruled it, just wondering.
I would say MAYBE. One sure check is to fire all of your rounds through a chronograph to verify if you are on the high end, low end or middle of your SD. How can you verify that all three shots at 400 were not on the high end of your SD and at 500 your three shots were not on the low end of your SD without a chronograph? You could also shoot more rounds at each range but sometimes this starts to become counterproductive especially with a short-lived barrel. In this case with a 308 why not if you donít have a chronograph. As time of flight increases understanding the differences in muzzle velocity variation become more and more important with predicting results. During cannon fire I would have the gun crews mount a chronograph to every howitzer. When you encountered ranging errors the chronograph was a great tool to verify muzzle velocity against that particular firing solution. Having a round hanging for at times up to a minute with ranges several thousand meters away leaves you with very little room for controllable error mistakes. The same principles of eliminating controllable errors and understanding what effects those non-controllable errors bring to the table are an important aspect to the long range shooter. If you have the tools available, use them. Many times they will give you the answer and keep your head from banging against the table.