Really... Defies belief... Do you know if he was a novice?.
I've been Clay shooting for a little over 50yrs and never witnessed what you have described here before... A little worrying to say the least.
If you Google "Lego display cabinets" ... There are many possibly suitable display cabinets for Cartridges shown there... some from IKEA that may possibly work well...and reasonably priced....
Problem seems to be... that everytime he arrives at the Airport he finds someone to argue with at check in... and misses the flight he's supposed to be on.
That's the most accurate and sensible reply i have seen on this whole farce or should say topic... Gizmos could help if your new to the Sport and need a basic understanding of "Lead"... but most good shooters have a certain amount of natural talent and a huge amount of experience ( Cartridges...
Never a truer word spoken when it comes to gun fit....The number of times i have seen this being the.... New and Different Gun purchase means of ascertaining if its the "Right Gun for me" before handing over the money ,,,,is frightening.