Good Ol' reliable Black Powder

I haven't been satisfied with the accuracy of my '94 Winchester 38/55 cast bullet rifle. My 50 yard groups seem to hover around 1 1/2 to 2" from solid bench rest with a 2.5X scope. I've tried 4 different molds, two gas check & two plain base, thee new and one antique. I've also purchased pre-cast bullets from Oregon Trails and Western Bullet Co. That's six different bullerts and with my home cast I've tried different alloys. Powders tried have included Unique, Reloader 7, Goex 2f and 3f and Pyrodex RS. Pyrodex has actually given me the best groups but only by a narrow margin, all in all everything has been about 3-4 moa with an occasional flyer but with no real clear winner among the bullets and powders tried.
So to the point here, I decided to try "fire-lapping" my bore. The instructions I decided to follow called for a pure lead slug so I case up some Ranch Dog 240 grain gas check bullets but left off the gas check and rolled 320 grit into the as cast slugs with no other lube. I was to load these into fired, un-sized cases and seat them as deep into the case as they would easily go without force. I was to use the lightest charge that would poop them out the muzzle. What smokeless powder and how much was left unanswered. I know smokeless powder can behave in unexpected manner, sometimes less powder causes more pressure, sometimes it just fizzles and misfires. With the bullet seated deep inside the case who knows that the remaining powder capacity might be.
The answer became obvious, good ol' reliable black! Black powder always behaves predictably. More powder always gives more pressure, less always means less. My experience with 60+ years of muzzle loading told me that it would require very little 3fg to pop the bullet out of the bore. The smallest Lee powder dipper was supposed to throw 4.6 grains of 3fg and I found it actually throws a bit under 4 grains. Would that be enough? Before loading up 20 rounds I decided to test fire one. With the muzzle hovering over a 3" thick slab of split cedar firewood I squeezed it off and somewhat to my surprise the bullet penetrated an inch and one half into the soft wood. A hard cast bullet would likely have gone farther since the bullet deformed and turned partially sideways.
Four grains of 3fg is not a load I'd take hunting but it certainly is not a load I'd care to be shot with. [smilie=l: