I'll agree with everybody else. If you have to THINK about the lead, then you are not focused on the shot at hand. Practice, Practice, Practice. My best advise would be to pick out one type of shell and stick with it. If you go shoot skeet, it will throw you off with the lead shot. If it is any help, I shoot 1 1/4 lead reloads from March until the end of good dove hunting. Then go back to winchester super x steel 4's until March. I will sometimes switch shot size in the winter for other game but shoot the same velocity. don't mean to brag but two of us get mad sometimes if we miss one bird out of a 4-5 bird flock. Two of us have cut down 6 birds many times. There are just too many variables for a straight answer. But if I could offer one suggestion: Shoot the same shells each and every time and you will learn to point your gun instead of trying to guess where the shot will go. If you want realistic answers: pass shot in front of you 35 yards out: about 2.5 feet. Over you: about 2 feet. Coming at you above but not interested: about 1.5-2 feet. Landing from the front: shoot their feet. Landing from the side: give them aabout 1.5 feet. passing over the dekes thinkin about landing(3rd of 4th pass) about 1.5 feet. The upper birds when the flock lands: shoot the feet. The lower birds after that volley: shoot the heads. If they're flying away: shoot the butts. These are not exact figures, only compiled from a point and shoot method. Want to add in another equation? Which bird is your partner shooting at? News story at ten.