Agree risky shooting factory ammo that far on an animal with SD on the 147 ELDMCheck my math? Shoot holes in it - explain how you can measure wind perfectly (because that is what it takes to hit at that distance) AND be sure it doesn't change in the nearly 3 second TOF. Every one mph of wind blows the OPs bullet nearly 20" - that is twice as large as the vital area of an antelope. Again, if you shoot 7.5 inch groups at that distance (1/2 MOA), you will have a 100% chance of a miss if you miss the wind by .44 mph. In my experience, the wind almost never stays within .44 mph over a 3 second period when its average speed is 6 mph.
I shoot every day at LR; shot today at 784 and 1183 so I am speaking from experience, not a keyboard. I didn't even mention the fact that you need extremely low SDs or you will see vertical error as well. The factory load mentioned has a MV of 2695. What if it was only 2690? You hit 5 inches low, but you still have a 50% chance of hitting because half your bullets are going to hit above your center of aim. However, once your MV deviates by only 10 fps, you have a 100% chance of missing due to vertical error.
Maybe James can tell us how well his students do at wind estimation. Like I said, if you could measure wind perfectly using nothing but mirage guys like @DocUSMCRetired would not be spending his time trying to come up with a better solution.
Not what I do
My experience 38 years shooting long range military and civilian 3-6 seconds wind change
If he did not hit on the 1st round my guess is second would have been over or under
Was good wind skill good ballistics and some luck at that range no doubt but again it worked good for him
I've seen folks wound at 200 yards so distance is up to the experience of the shooter and equipments
I told him the animal could have walked during flight time, but I teach that in class
Any way all good.