I don't shoot jacketed bullets. These loads are cronoed from a 5.5" Bisley using a 300gr. hardcast bullets from CPB or Beartooth, but hopefully this gives some idea of what you might get. For a medium load I use 10.0 of Unique and get 1100 fps. For my hunting load I use 24.0 of Win 296 and get 1320 fps with a vel spread of 15 fps.
For the med load I'm using Win WLP primers and for the hunting load I use Federal 155 mag primers. Speer manual gives 23.0 of 296 w/ 300 jacketed bullet as max. I find that going to low w/ 296 gives extreme spreads so maybe start at 21.5 grains and work up watching for pressure signs.
Hope this helps.