Sometimes I shoot a three shot group set the gun aside and rotate other guns while it cools, when that gun rotates around again I shoot another three shot group at the same target so I have a six shot group, rotate again and so forth, sometimes I wind up with 12 or 15+ shot group. That will tell me on average what I can expect from that gun with a particular load. One or two seperate three shot groups by themselves can be very misleading. Other times I shoot a couple five shot groups, if something looks promising I'll repeat it over and over till I'm confident with that load. I wouldn't go to a match banking on the results of a couple three shot groups.