You must first establish a baseline for your particular antique revolver. This baseline includes "slugging" the bore of the firearm in question. The mandatory reason for this is due to the black powder or antique era being a "non standardized" era where each manufacturing firm manufactured their own variation of any given caliber at that time.
Before you even attempt a smokeless recipe for your "Antique" firearm you must match the bullet to bore. Don't just assume any given mold will cast a bullet that matches your antique bore. This is an advanced stage of shooting and must be very carefully performed. Only "pure" lead bullets and mild loads after you have the gun checked for cracks and flaws of which there can be many. I've seen many hairline cracks in antique cylinders and on top breaks you can find hairline cracks on the barrel at the thin area just above the barrel breech. This area is under the most stress with discharge and is also directly exposed to the high temperature powder flash from discharge at the barrel to cylinder gap.
Changes in bullet size. Even soft lead bullets "will" increase pressure dramatically using smokeless loads. Especially if the bullets don't match your specific revolver. I've seen and mic'd variances in bore dynamics (groove diameter) in black powder era revolvers, specifically in .41 calibers by as much as .029 from the same caliber! That's a .41 caliber that mic's at .381 caliber. Scary stuff. The industry got away with this buy using black powder only. Use smokeless in one of these grossly undersized bores and you will burst the gun. Never knowing why cuz you never mic'd the bore!
Changes in bullet size by only .002 can increase performance by as much as 15% with just black powder use. I've proven this at the range with a chronograph and in the 44/40 caliber using 200 grain pure lead bullets of the same design. One being a .427 bullet and the other being a .429 bullet matching the .44 special and .44 Mag caliber bore dynamics. So the antique era is a specialized era and requires that you do your homework. No smokeless era shortcuts....You know, like getting in line at the gunshow and just buying a one size fits all box of bullets. Can't be done safely with antiques. They are from a different era all together. The smokeless era introduced the era of Standardized measurement that we were born into.