Second, because no two patterns are truly alike, it's important to shoot more than one to see how a load performs. We shot 10 patterns with every shell we tested. We actually started out shooting 25, but decided that after 10 we had reached a statistical point of diminishing returns and it took a lot less time. We had the advantage of an underground, windless tunnel, and endless roll of paper that automatically gave us a clean sheet of paper after every shot, and a computer that could count and tabulate all the holes in a sheet in three minutes. Without those advantages, patterning is a long, boring process. You can get away with shooting three patterns with the same load at a bare minimum to see what it does, but is five is better, 10 is best, more than that doesn't seem to be necessary.