I believe one of the many factors hindering CB shooters from making as much progress as we might make otherwise it that we draw conclusions about whether a tested “improvement” is really better without shooting enough groups.
For example, if we want to find out if 16 grains of Old Blaster powder (Load X is better than our standard load of 15 grains (load A). We might load up ten rounds of each and shoot a couple of ten shot groups. If the A group measures 1.3” and the X group measures 1.6” (23% bigger) it is tempting to conclude that we had better stick with A because X is clearly worse. Joe Brennan has told us that this is a shaky conclusion which we shouldn't have much confidence in based on statistics. But statistics are hard to love. However, yesterday in the thread “Testing Bullet Lubes at 3,000 fps” mtngun presented a lot of date on actual shooting results that lets shooters see why Joe is right and the conclusion that A is better than X really is shaky. And it can be seen without opening a statistic book. At least any shooter can see why it is shaky, who will really look at the range of results of the ten 10-shot groups fired, keep an open mind, and do a little thinking.
Even if we eliminate group three of mtngun's groups because the flier may have been caused by the scope adjustment, the other nine groups ranged from .98” to 1.95” (99% bigger). There is no logical reason to believe that if the shooter above testing A and X fired eight more groups with each Load A and Load X that those groups wouldn't vary in a similar way. Expecting to make a valid decision about A vs. X with just the first two groups fired is fairly likely to be wrong. I am not claiming that it takes ten 10-shot groups with load A and X. (Certainly if group X had been twice as big as group A, the shooter's conclusion that load A was better would have been on solider ground.) But I am saying that we are kidding ourselves a bit that the original 20 shot experiment allowed a solid conclusion. When this is considered in conjunction with the fact that from reports here and in the Fouling Shot it is clear that many shooters are making such decisions based on two 5-shot groups. So it isn't surprising that we sometimes seem to be chasing our tail in the pursuit of improving CB shooting. John