While not really a solution for my conundrum, WOW that is something I was not aware of, and is possibly the neatest thing I've seen in awhile! Those would definitely be stupid fun! Are they hearing safe? Would they be safe to use in a 4-inch Security Six? Do you need a reloading setup for these? I'm thinking a backyard shooting gallery that doesn't freak out my dogs or neighbors, like using CB caps in a .22 rifle.
Edited to add.
(You have no idea the force of will it took not to immediately order 100ct of each of those, only the $20 shipping and haz-mat fee stayed my hand. And checking my account balance. )