I settled on some buck and ball loads, I tested them out in my single shot as it's my experimental load gun before trying them in something more expensive.
I'm pretty pleased over all, 2" group with the balls at 25m offhand with only the front bead.
No signs of any pressure and using the ballistol cleaning method they are not a lot of work cleaning the gun afterwards.

https://youtube.com/shorts/7Kqyx4afUBk?feature=share