A sample size big enough to satisfy the brilliant Dr. Jones?
That would seem a tall order.
We've discussed this quite a bit here and opinions vary widely, but I'll amplify briefly and then stand aside for the inevitable hailstorm.
It finally occurred to me, after trying to reconcile the work of past authors and that of Jones The Great, that we are trying to analyze a 3D system with 2D snapshots.
And that's the key. Patterns are snapshots. It a 2D representation of one distance downrange.
The problem is that shotgun pellets do not fly straight. Nothing flies straight, even a sphere, unless in a vacuum and even then its path is bent by any gravity field.
Look through a bag of reclaimed shot sometime and try to imagine any of that flying even remotely straight through the atmosphere at a speed starting near sonic and then decreasing to half that at 40 yards.
The pellets once given an initial vector, do not stay on that path. They travel in a helix, do little whifferdills, arcs, and they slow at various rates. The pellets are moving around inside the shot cloud and the only thing that can be said for sure is that the average diameter of the cloud is expanding.
What you see at 25 yards as voids and patches may look entirely different 5 yards further downrange. The clumps are expanding into the voids, and in doing so likely make different sized voids which are then expanded into.
It defies analysis.
I've come to the conclusion that pattern analysis is limited to the size of the pattern at the measured distance, and any attempt at quantifying the 'quality' of the pattern is just a fools errand.
What you might see on a pattern plate is not what a moving target sees as the shot cloud passes.
My fine condition of copy of Oberfell and Thompson is for sale to the highest bidder. Small bills, in the dead of night, no record kept of the idiot previous owner.
