This is a good example of how adding just a single additional shot then three, can change the whole group. Granted now this is at 50 yards and with a scope off a single bag rest. I was testing Black Mag3 and some conicals in the White. But see what happens when you are thinking ... the first three are so good, lets flop a couple more in there. Like Underclocked said, for some reason your mind blows it...

I now shoot five shot groups when checking anything. Five shots might give me a bigger spread, but I really do not care. It also tells me what the rifle is more apt to do.