You didn't tell us anything about your rifle, what caliber, range equipment you are using or reloading practices. Number of shots in test groups is way down the list. For instance, I have a benchrest rifle that I know is reliable, that I shoot off of a bag/rest setup that is a known quantity, referencing flags as I shoot. If the wind is easy, and I am at the beginning of tuning with a new barrel or reloading component, I see no reason to shoot more than two shots in a group. If a two shot group is not up to standard, a third shot cannot make it any smaller. After I have determined that something interesting has happened, I will shoot groups of more shots, with the understanding that the more shots there are in a group, the greater the certainty that they will not all be fired in identical wind conditions, enlarging the group for reasons that have nothing to do with the quality of tune. Loading at the range, is the only way to fly. Many shooters don't use flags, don't load at the range, use shooting styles that are not suitable for their rifle and/or caliber, live with barrel mirage, and are overly concerned with things that will never show up on the target. Like I said, number of shots in a test group is way down the list. To really learn anything from a tuning session, you need a reliable system. If you like, tell us about yours.