"I've seen something similar that was used to adapt police service revolvers to Simunition cartridges; the idea was, these rings would be inserted in the forward end of the cylinder to prevent a full-length (LIVE) 38 Special round from being chambered in that revolver by accident, during force-on-force training, but they would still allow the shorter 38 Simunition cartridge to be chambered and fired. My best guess, at least; ring any bells? "
Bingo, that's it. Your insightful reply got me on Google with a direction to search. I did a lot of Sims training (exclusively with semi autos) and got these for the occasional revolver use. Thanks. It's a bear getting past 60. Memory is indeed the second thing to go.
