This one was made in Nuremberg by Hans Stopler, so I suppose raise a stein to German engineering. Once again it never fails to impress. Revolvers wouldn’t become commercially successful & produced in mass quantities until the 1800s.
https://www.thefirearmblog.com/blog/2016/11/15/worlds-oldest-known-revolver/
Forgive my ignorance, but where would the original owner have bought bullets for this?
The bullets would have been round lead balls. You could cast them yourself fairly easily. I would imagine the person who owned this would have been rich enough to have their own personal armorer to cast bullets for them.
Here’s a mold:
Then to load it you would follow the same procedures you would follow to load a normal flintlock pistol.