Formidilosus,
Actually, you explained it very well, but the photos help a lot.
One of the reasons so many half-inch rifles exist on the Internet because their owners never shoot more than 3 shots in a group---becuase they "know" sporter-weight barrels won't shoot when hot.
Even when doing preliminary load work-up I shoot at least four shots these days, as 3-shot groups are just too dependent on chance. When further along I shoot 5-shot to 10-shot groups.
The only trouble there (as I mentioned earlier) it that I can rarely write up those groups in my articles, because so many shooters these days have no real concept of accuracy, since their only frame of reference is 3-shot grouops. Hence they're not impressed with a 10-shot, 1" group--which is outstanding accuracy from a hunting rifle.
