I was recently looking at some of my books, and a 10 ga 3.5 and a 12 ga 3.5 shells hold almost exactly the same shot and powder, and close to the same pressure, almost all the 12 ga were faster though, even with the same shot and powder, doesn't realy add up, but then what is the point of shooting a 10 ga, if you can get the same shot out faster, same pattern and cheaper, maybe you should look into that, I think if your shootin that far away, your wasting shots anyway's, you caint tell me your taking three on a go around at 70 yards when I know it's possible to get three at 20, if so maybe you should be on t.v. instead of this website.