FWIW, today out on the farm I ran 24 rounds of Black Powder .44 Russian thru my Uberti #3 Third Model Russian top break, with no binding.
This bullet:
http://www.accuratemolds.com/bullet_detail.php?bullet=43-215C-D.png90/10 Beeswax/olive oil lube: pan lubed, bullet unsized. Bullets drop .430.
20 grains Olde Eynesford 3f
WLP primer
Starline .44 Russian case.
Cylinder still spun free at the end. This is a later model that does not have the Cylinder beveled. I've tried several combinations, this one is by far the slickest. All rounds hit in a 4 inch circular group at 10 yards. Greasy muzzle and cylinder face.
(24 may: Did 40 rounds today, no binding. rested the barrel this time, got a 3" round group. Humidity over 75%, but I think this is a good match load now)