For 115gn FMJ my standard light target load was 4.0gn of Bullseye at 1.13". It's a load my Dad has been using for years (actually decades now) so I'm honestly not sure how much lower you could go.
Switched to 5.0gn of CFE Pistol with the same COL in the last year since I ran out of Bullseye and CFE Pistol was the only thing suitable in stock at the time.
Started at 4.8 and went up to 5.6, and found 5.0 works the best for me. 4.8gn was enough to cycle the auto's fine, so there should be room under that if you're developing an even lighter revolver load.
Of course I'm now running out of CFE Pistol, but was able to get 4lb of Tightgroup, so it'll be time to start experimenting again soon.