Ralph......As always, you are right on top of something! What many shooters don't realize is a short forcing cone is best when using cut wads in a load, whether black or smokless powder. Contrary to what some have seemed to find, I have had no trouble with plastic over powder wads, like the BPI X12X, when using black. For shot protectors, I have used paper dime roll paper, teflon wrappers, and the fine old Alcan "Kwik-Serts".
I have also found that a .200" nitro card (when you can find them) are as good as the X12X.
As for buffer.....Greener used bone dust and helped large shot patterns a great deal. What I have found is the spherical buffer from Precison Reloading is much better than the poly buffer from BPI.......it does not "pack" (but flows) and it does not raise pressure as much. I never use any buffer in fixed ammo until I go to #4's and larger. Buffer, plus good hard shot, will deliver better patterns, whether using black, a subsitute, or smokless. I know various outfits make cut wads today, but the best I have found are the Alcan Feltan-Bluestreak or pure cork. Many shooters do not think the blackpowder guns will produce very fine patterns! Not so.....some of the best patterns ever produced (and recorded) were with chamber-less blackpowder guns and thin brass hulls.
The other thing I see (and laugh at) is the trend of American shooters over looking some of the very fine American double guns, thinking everything the Brits are better. My favorite is a hammer gun made by Ansley Fox's father and sold special oreder at Abercrombie & Fitch in New York in 1900. It weighs 10 pounds, has heavy "Star" Damascus barrels, double under lugs, doll's head, and reinforced frame.......and was made for 3" brass hulls (rare today). I looked a long time for a gun like it! It was built as a waterfowl gun and can be seen in the Tech Note section of Dixie Slugs. Its 32" full & full barrels will throw patterns with #4's, #3's, and BB's that few modern loaded factory shells will match. The gun was set up for 4 drams black and 1 1/2 oz of shot.
So....What I am trying to say is blackpowder guns are a pleasure to use! Even buying a modern single barrel like a NEF and using black! What's nice about doubles ans singles is the barrels pop off for cleaning.
The other problem is finding blackpowder now days! We even have a few special customers that we load 2 1/2" 12 gauge blackpowder shells for, but they are expensive!
Regards, James