I have an American Bulldog that looked unfired when I bought it ( could have just been very well cleaned up a long time ago though )... mines chambered in 44 Bulldog
I shortened 44 special cases & used a light weight soft cast bullet & started with light loads of Trailboss... I was conservative, & my 1st loads too light, causing the primers to push back, & not re-seat... I have some soft lead round balls I plan on loading as well, when I get back at it...
just wanted to tag along, for if / when you decide to try shooting it