Many years ago a buddies father thought he would like to check out my MP5K. I show him the selected lever & charging handle, the run it in semi, bust & finally a dump. From their the same with its suppressor. I brought 500 round figuring to let him have his fill. He shot 30 rounds & was ready to go to lunch.About a month or two back at the indoor range, I had a bay about to myself for a while which was great. Old man comes in with a pump action shotgun, and this guy was probably 5'5" and pushing 120 - a small guy. Launched one slug down range and it blew him back a few steps. Wasn't stoked to be right next to him. Fortunately (?), he couldn't seem to rack it by himself, so a range officer helped him figure things out. Pretty sure he paid $20 to fire about 3 shots before leaving. Maybe he was just efficient. Maybe he was in over his head.
At lunch he asked about ownership, I explained transferable & Dealer samples. He was really taking back at the cost of transferable (he was a millionaire). About a month later he ask for me to met him for lunch. At lunch he ask what other machine guns I thought were worth having now that he upgraded his FFL to include the SOT.
When his H&K MP7 came in he asked about the optic on my MP5K working of his MP7. After sighting the optic in he might have dumped 15 rounds.
Prior to his SOT he had a FFL & importers license. He formed Euro Gun Imports to import Double Rifles. I think the SOT & FFL was just something else he could do with his son. What was crazy about the double rifles was I was the one who suggested a red dot for his older eyes. Every rifle he had for his personal use I would sight in. More times or not older guys only want to pull the trigger when it counts.