SD vs Accuracy

[Walt]

In the Wolfe Publishing online article that came out yesterday there was an interesting story on test-firing a Smith .45 Colt from a Ransom Rest with various loads. What I thought was most intriguing was the relationship between standard deviation and accuracy. Lowest SD is not an absolute indicator of best accuracy but it suggests that a relatively low SD, such as between about 5 and 15fps seems to do the best.

[Scott Tschirhart]

It makes sense that lower SDs would lead to better accuracy. But I am not convinced that there is a direct correlation, particularly at typical handgun ranges.