As stated, it has to make 400fps in a revolver and can not break the 1400 fps mark out of a rifle.
The min power factor in SASS is 60, and you get this by taking the bullet weight, times the speed of the bullet, then divide by 1000.
So if we take a lee mold bullet, then 452-160-RF is about as light as we can get to minimize recoil, and in a flat tip design so we can run this loaded round in a lever gun mag tube as well, we just take the 420fps to be on the safe side so it does not fail an ammo test, times it by the weight of the bullet, and come up with a MPF of 67.2 for the load.
So if your looking for a SASS 45lc load, again the lightest flat tip bullet you can find, and then ladder load the powder with fiber wads to keep the black powder compressed in the case under the bullet, and depending on the type of powder you are using (don't use a black powder substitutes, since they are worse on the gun for rusting than real black power), you need to come up with a power amount that has the the bullet going the min speed, plus a few extra FPS (so it not going to fail an ammo test with the bullet not going fast enough in the revolver). From here, run the same ammo that you just did for the pistol load amount of powder amount for the pistol, and run is through the carbine to make sure it not going faster than 1400fps out of the carbine.
Truth be told, for black powder shooting, I just end up making black powder to run in the guns, verses buying store bought Goex instead (Goex got expensive in the past decade with all the shipping and storage regulations, since its a explosive, and not a propellant like smokeless powder) .
I will screen it out to around FF~FFF, and once I have about 8lbs of it mixed together to uniform it/repack it back down to 1lb containers for storage, will just develop a load for that batch of powder to hit the needed marks for the revolvers, the shotguns, and the carbines.
Note, all the smaller grain/baby powder type powder that will fall through my final size testing screen each dried batch before its batch unified, is just put in the next stove batch to be re-screened again.
https://youtu.be/dj-HGHzCFos
So between casting my own PC bullets with DIY Bore butter in the wax groove, and making the BP at well, I'm less than $.02 a round in the end.
If you take the old Goex Black Dawge factory ammo (that as too hot and recoil brutal to really run in SASS), they ended up being close to a buck a shot isntead (about what you will have to charge to make a profit loading BK rounds with bought powder/cases/ even BP specific waxed bullets, then ammo boxes to sell out right).
DIY bore butter, since its needed to keep the black powder fouling in the bore soft so the next round can push it out; plus works well at lip balm as well.
• 1 part bees wax (any hobby store)
• 4 parts Olive oil (Extra Virgin for extra performance -- NOT)
• Dash of food color (various colors depending on my mood)
• Dash of Spearmint/Wintergreen/Peppermint oil (whatever the wife won't miss)