I really prefer smokeless powder to black does it make any difference in the end result. Also could we use the substitute pellets instead of black powder.
Yes. Smokeless and and substitutes can be used in the modern reproductions of the Sharps, Rolling Blocks, etc.with similar results(velocity, accuracy) given the proper choice of powder, and attention to burn rate, pressure, and case fill. Modern, jacketed bullets can be used as well. Keep in mind that some of the older action designs may not have the strength of the modern Marlin, 1876 lever action, and T/C's which can withstand higher pressure handloads as well as the hotter(higher pressure) factory loads in 45/70. I initially used smokeless powders and jacketed bullets in my Shilo Sharps with good results, but soon converted to black powder and lead cast bullets. I found the satisfaction and enjoyment of shooting these rifles as they were originally used was greatly enhanced.