This came out of a discussion on the Fox site regarding patterning of non-tox shot at long ranges. Might be of iinterest to others interested in long range performance and I'll copy it here fwiw.
> Anyone interested in long range patterning of Supers etc might get one of these template gizmos made up. Made of 1/16" butyrate by a friend in the plastics biz who has a laser cutter - but a template could be made by a careful craftsman with a jig saw. Sorry for the lack of contrast on the carpeting but the template is transparent. I've put on a piece of blue tape to show the difference between the 30" diameter outer circle, and a 20" diameter inner one that's particularly useful to check for a so-called "hot center" (pellet density in the center 20" circle versus in the larger/standard 30" circle). That blue tape is 5" long.
In practice you place a mark on your patterning paper at the normal 40 yards, shoot at the mark with gun held to the shoulder in normal position, then overlay and center the template over the BULK of the pellet pattern. Use a table and draw the two circles with a pencil. That will let you see the center of the pattern versus your aiming point, and see how far your point of impact deviates from point of aim. Using a Super-Fox or something like an thaca Super 10 - I'll normally just count the pellets that missed the 30" circle and subtract from the average number of pellets in the shell (less counting). Then do the math for pattern percentage. You should do a "composite" of 3 or better yet 5 shots and average to get a good count - owing to an aberrant shot that might produce a random high/low count for some reason. Trying to determine pattern percentage with only one shot will often give an erroneous % number.
For our long range experimenters .........