Two hundred yard ranges I shoot at, they are so soupy with mirage, even with contrasting backing targets, bullet holes get to be invisible. The mirage will flicker, maybe you will see them, maybe not. And I am talking about 30 caliber rounds. Camp Perry had particularly good visibility, I could always see my 200 yard rapid fire holes, sometimes my 300 yard, through a spotting scope, so what you can see depends on the location. A guy brought out a Russian ship spotting scope,you used both eyes to look through the front lens. It was a huge front lens, about 24" in diameter. Everything was so clear, I was looking at Rodriquez and Vaile range targets from where we were at, and that mirage was so clear, so visible, and it washed out everything behind it.
I have purchased a number of $200 scopes recently, optics today are all good, much clearer than they used to be. But even the best lens can't see through mirage.