I use a home-cast SWC bullet with a gas check that weighs about 115 grains sized and lubed. It's from an old Lyman mold I bought used in about 1980. I shoot it over some Unique. All my .32-20 brass is Winchester. The late Skeeter Skelton, gun writer extraordinaire and mentor to many of us here, used 4.5 grains of Unique under a cast 115 grain bullet. I tried it, found it to be great and shoot roughly to the point of aim in the few handguns and one lever gun I have owned in this chambering, and never experimented afterwards.
There is some warm data published. Don't use if for the K frame S&W .32-20's, it's too hot.