Howdy gents. I do alot of work on these little gems and I can assure you that if you use modern ammo in them they WILL sooner or later blow up
If you want to shoot it use the CCI CB caps, They make them in longs and shorts. I've been a antique gun gunsmith since 1951 and I have seen a good number of fine collectable guns like this turned into junk by folks using modren ammo in them. You have a really nice piece, treat it right as you are
after all only a temporary guardian.