Suppose you have two batches of pellets, or .22 cartridges, or two sets of handloaded ammo, and you want to decide which one is the best for your competition shooting. You can compare them by testing, i.e. fire some shots and observe which one is best. But what do you have to measure from the resulting holes in your target, and how do you use these measurements to get the ‘best’ answer? Furthermore, how sure should you feel that you are indeed picking the best batch? After all, due there is some randomness in the groups that you shoot. So when you repeat the test several times, it is not always the batch that is ‘really’ the best one that will win.

Using Monte Carlo simulations of shot groups as a basis, this article from the archives covers three issues.

  • From several known measures for shot group tightness measures, which one is the most often correct when you are trying to identify the best batch (no matter how small the difference).
  • What is the best way to spend a given number if shots: all in 1 group, or several sub-groups?
  • Using a statistical test to find out if the differences between two batches are statistically significant.