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McShooty · April 13, 2012, 10:27 PM

The only way you can tell if your load will be good every time you shoot it is to shoot more than one group. Accuracy naturally varies from group to group and is subject to statistical analysis. Shooting one group is a real good way to come to an erroneous conclusion. More groups will improve your choice and is NEVER a waste of powder or bullets if you wish to have confidence in your results.

This need have little to do with shooting talent at the bench. Assume zero shooter error and the groups will still vary due to load variation and rifle performance from shot to shot. It would be nice if one group with each of two loads would indicate which is best, but that is generally impossible in a practical sense.

The original post wanted to choose between two loads that differed by a small amount in powder charge. One appeared to be better than the other, but one group is not enough. If you disagree, how much would you be willing to bet that the next pair of groups fired by the original author would not be reversed but show the same results. Would you put $1000 down on it?

Shooting forums are full of reports from folks who fire a couple of decent groups one day, and on the next trip to the range the groups open up somewhat and they wonder what is wrong. The answer is that there may be nothing wrong. They are simply living out the statistical variation of their gun and load on different days as time goes on.

April 13, 2012, 10:27 PM	#12
McShooty Senior Member Join Date: January 4, 2012 Location: Northern Missouri Posts: 480	with each would The only way you can tell if your load will be good every time you shoot it is to shoot more than one group. Accuracy naturally varies from group to group and is subject to statistical analysis. Shooting one group is a real good way to come to an erroneous conclusion. More groups will improve your choice and is NEVER a waste of powder or bullets if you wish to have confidence in your results. This need have little to do with shooting talent at the bench. Assume zero shooter error and the groups will still vary due to load variation and rifle performance from shot to shot. It would be nice if one group with each of two loads would indicate which is best, but that is generally impossible in a practical sense. The original post wanted to choose between two loads that differed by a small amount in powder charge. One appeared to be better than the other, but one group is not enough. If you disagree, how much would you be willing to bet that the next pair of groups fired by the original author would not be reversed but show the same results. Would you put $1000 down on it? Shooting forums are full of reports from folks who fire a couple of decent groups one day, and on the next trip to the range the groups open up somewhat and they wonder what is wrong. The answer is that there may be nothing wrong. They are simply living out the statistical variation of their gun and load on different days as time goes on.