The NA Schofield fouling problem is due to the lack of a decent gas ring because the cylinder is lengthened to accept 45 Colt and 44-40. The 45 Schofield (original) cylinder was shorter. I have Russians as well, and the Uberti made 44 Russian cylinder is longer than the original, but a bit shorter than the Schofield, but it still doesn't like black powder.
That being said, I have original S&Ws in 44 Russian, and they don't shoot many rounds without fouling out either.....
Blowback, which the 44-40 case will reduce greatly, helps most in the rifles.