I can't narrow it down to much so we will keep it kind of general. with 100 gr you end up with the velicity and ft pounds about equal to a 44mag out of a Rugar with a 7.5 inch barrel at the muzzle. the figuars are from my Omega nd Rugar I am not sure how much that 10 grs drops you but a 100 will do when you hit the right spot.
Also since I shoot the same gun powder and bullets I would suggest you try going up the powder ladder; I have two loads for SW's the 50/40-200gr shoots good at 100 and at 150 for me the 250 at 90 and 130. Lee