Originally Posted by Dr. Vette
I'd wonder more about the wind.
Last year when shooting my elk I was on the edge of a small rise overlooking a very flat meadow. The wind seemed in my face, directly on, but in reality I discovered it was coming at 45 degrees or so, and then up the edge of the rise, making me think it was head on. Thankfully I made corrections and still got the elk.
So, the wind might have tricked you.
When it comes to windage errors elk are very forgiving due to their size. You can be off 18-24" on a broadside shot and still put it on target well enough for a clean kill.
Measure an elk carcass from the last rib to mid neck and you're going to have a kill zone that is roughly 3-4 feet wide depending on the size of the animal.
When you consider this shot was sub 600yds it would take a tremendous error in wind adjustment to get a complete miss.
Taking the angle cosine multiplying by 587 I get a true linear distance of 508 yds. Sinee he held/set for full value he was off roughly 26" in doping the drop.
If the aim point is mid depth that's about 13" from the withers which would mean the bullet probably sailed 8-12" high over her back.