Lead depends on shooting style. I can break high four at least four different ways. Sustained lead where I start ahead of the bird, you pull out in front, get your proper lead and maintain it as you pull the trigger and continue that lead well past when the bird breaks. Swing through lead, where as you pull through the bird, pull the trigger as you accelerate the gun past the bird. I can spot shoot the bird without moving my gun. Just get the birds flight line and pull the trigger at a set distance before the bird reaches your gun, a timing shot. And last, my all time favorite way to shoot. I flinch, right before I am about to pull the trigger, scare my squad mate into hysterics, recover and track the bird down for a very late shot. Sometimes I use the flinch and spot shooting technique together if I am lucky enough to flinch in the right direction.

I am sure others have their own way to do it. Being able to shoot the bird multiple ways comes in handy. In the field I rarely get to use sustained lead but often a shorter lead with a pull away component. From a mathematical point you can compute the needed lead at station four high bird as 34-39” depending on bird launch speed. But most can not accurately judge 34-39” at 21 yards so it becomes personal. What do you see? I’ve known good shooters who only see daylight in front of birds and others who look like 5hey will ride a bird off into the sunset.