SE-Okla.shooter is right on the money about flinters.. Flinters have been my game for better than 28 years and i wouldn't trade a tea spoon of Black for a pound of pyrodex..
I use a deer tine to sharpen my flints.
Each long gun has it's own 'Shootin Bag' N' Horn. The tools particular to each gun live in the shooting bag.
The one pistol I have shares the same round ball as my .62 cal Nor' West Gun, so I only use that pistol when I use the long gun that is it's match. That Shootin' bag has deer antler measures for both guns.
In a rifle the twist is measured out, and then the projectile is used to match that bore's rifling.
Twists varies and some companys offer different rates of twist in the same model of guns.
I don't believe in moddified twists guns, said to be able to shoot both conical and round ball. I see it as you buy a slow twist gun for round ball and a fast twist gun for conicals.
Some middle of the road twist to shoot both kinds is just a poor choice. But that is how I see things.
I don't own a long gun that shoots caps, but have 2 six shooters that do. These never see any pyrodex either.
I see that as if my flinters can't set the stuff off, then the Black is just faster, and to me better.
30 years ago when the Golden Powder first came out and before the inventor blew himself to bits, I tried it and didn't like it then and then I had guns like yours now.. I had TC Hawkens and the like back then, and I didn't like these new fangled powda's in em then..
Back then my elk load would have been 120 grains under a maxi ball made by TC. That loading was as stiff as anyone needs to kill elk.
Anything over that is a fools folly.
Back then target loads for paper were 40 grains of FFg (2 F) Hunting loads were around 60 grains FFg for deer, and in New Hampshire where all shots are usually pretty close in the thick woods.
In a general way the faster you push a ball the more off aim it flies..
So a lesser charge placed well is a better game getter, than a fast off target charge will ever be..
Too much powder does 2 things..
1 It adds to recoil by no more than added weight to the load.
2 A point comes where the bore is too short to burn the powder in the bore, and burning the powder out of the bore is pointless.
3 If you push a soft lead bullet too fast it shears from the rifling and the result is exceedingly poor accuracy and a leaded bore.
One way to find how much powder a given gun can burn, is to place a old white bed sheet on the ground somewhere ahead of the muzzel.
Then you start to load from say 50 grains of FFg and inspect the sheet after each shot, and add 10 grains to the next load, to where the point comes you find unburnt powda..
When you find that point drop back 10 grains and try it more on targets too see if you can hit a group.