Spent six years doing technical and consumer research, and statistical analysis of the resultant data. Curious to see if it is possible to extrapolate 3 shot group size to 5 shot group size to 10 shout group size, etc.
The general guide line is 1/2" 3 shot groups = 0.75" 5 shot groups = 1" 10 shot groups.
In other words, what most shooter call 1/2" guns are actually 1" guns.