I have been shooting BP for years as a hunter and at the Range or Rendezvous.
The load depends on what you are going to do with the Rifle. Target Shoot, Hunt. I shoot a 45 Flintlock very often. I use a 440 round ball and a .15 patch and 50 grains of 3F Blackpowder.
If I was into serious competition I would likely use a 445 roundball and maybe a .20 patch for a really tight fit. It will close up a group at 100yards. If I was hunting I would add about 20 grains of 3F. I always use Blackpowder and none of the substitutes. For that info you will need to ask someone else. Most muzzleloader cap locks use a #11 cap. Some pistols us #10. If this is a "INLINE" I really can't help you but it may take a Musket cap.
This is the fun of BP is finding the right load for your gun. Try lesser or more powder, and try different thickness of patch and try either the 440 or 445 round ball. The tighter the fit the more accuracy at longer ranges but don't make it so tight that you need to pound the ball down the barrel. Pounding will distort the round ball.
Hope this helps.
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