Couple of questions on your objecives.

Do you wand to do comparitive patterns - this load/gun vs that load/gun? Do you want "some idea" of what patterns look like? Do you plan to makd decisions as to loads and guns from the patterns? Are you familiar with the book, "Sporting Shotgun Performance" by Dr. Jones, along with his free Insights pattern analysis program?

Depending on above answers, I may have some suggestions.