I have kept this Bad Boy loaded for 3 years. It fired fine, all five cylinders, full power.
The revolver was kept in a drawer, in the humid NC mountains. There was no corrosion in the cylinders.
This was with 30 grains fffg black powder, CCI caps. No wad, no wax or grease sealer on the ball, or on the cap.
I have kept my 1860 Colt Army loaded for 2 years, and it also shot fine.
I know the CCI caps will keep for quite a while. I got my brother interested in black powder in 1978. He bought a cap and ball pistol and a pound of powder, and CCI caps.
Then, he lost interest in the hobby.
Last year he drove up here and we got his old gear out. I figured the old caps would be unusable. We went ahead and loaded his pistol up with his caps and powder, and it shot fine!
We fired 30 of the 31 year old CCI caps that day without a misfire.
I believe you could keep a revolver loaded for decades and it would shoot fine.