I don't mess with cast,but i am a handloader and owner of the Win M1895 in 30/40 Krag with 28in pipe.Here are some of my handloads for the 30/40 Krag.
130gr Speer 45.5grs of IMR 4064 for 2900fps-2428fpe
180gr Speer 47.0grs of H-4350 for 2500fps-2497fpe
220gr Nosler 43.0grs of H-4350 for 2200fps-2363fpe