Heeled bullets / molds - Old West Bullet Molds
https://oldwestbulletmoulds.com
I have a number of their molds - pricey but top quality all the way.
On .36 caliber C & B - remember the bore is .375". I use both the Kirst cylinders (gated) and the Howell drop in cylinders in my '51 Navies and '58 Remington Navies. The .36s require a .375" soft lead bullet with a .358 "Heel" - the heel goes in the case mouth and is crimped - remember that these are "outside lubed" bullets. Old West makes a 125 and a 150 grain mold. They also make a special adjustable shell holder and carry a special crimp die for crimping the "heeled" bullet into a 38 Colt Short & Long casing. If you are using a conversion cylinder in a .36 and don't have heeled cartridges or the ability to make them, a standard soft lead hollow base .359 - .360 wadcutter will work with decent accuracy as it is has the ability to expand some when fired to fit the .375 bore fairly decently. The only "conversion" revolver that I have that takes a standard 38 special lead cartridge (.358 slug) is a Uberti 1851 Navy R & M Conversion which is made with the now standard .38 bore (.357).
On my Uberti & Pietta .44 revolvers, Colt/Remington - I have Howell conversion cylinders for them. A standard .452/.454 soft lead bullet works fine. On all conversion cylinders - follow the manufacturer's recommendations for cartridges - there is no need to "push the limit". I normally use a 200 grain soft lead traditional round nose flat point slug and will sometimes use the traditional Ideal/Lyma 255 grain 452-190 or 454-190 round nose flat point. I use both 45 Schofield and 45 Colt brass - I don't shoot competition - some use the short "45 Cowboy Brass" (Starline) - all depends on what you want to try as far as brass and bullet design/weight.
I know this is an old post but am posting this info for reference only. Also - remember that C & B black powder revolvers are not considered firearms as they come from Uberti/Pietta. A "Howell"type conversion cylinder requires no alterations to the revolver - however if you gp tpship them, the revolver and the conversion cylinder must be shipped "separately". IF YOU ALTER THE HANDGUN to accept a "gated conversion cylinder" - such as a Kirst Gate Konverter cylinder - which requires alterations to the recoil shield (where you normally would use the "stock cutout" to put the percussion cap on the nipples - this has to be found out when fitting a gated cylinder so that the cartridges will slide in for loading and spent casings ejected out - the original design of the revolver has been changed and the new alterations have no turned it into a "firearm" that will need to be registered as such in the states and municipalities that require handgun registration - it will also have to be sold as a firearm if you should sell it/trad it/give away.
I enjoy loading and using "heeled cartridges" - lots of fun. I have no ties with "Old West Molds", but I have dealt with them a number of times and have been very pleased with their products and service.