A) do you have a reloading manual? Lyman has data but specifically notes that it is not for use in antique guns.
B) the very real problem that you face is that your gun - 1893 - is really meant for BP cartridges. AFAIK, the 45-90 was not loaded with smokeless propellant when your rifle was designed. Smokeless loads appeared in 1895.
There is a modern variant called the 45-90 Express; it is not the same animal.
C) Maybe you looked already....IMR's online data base has no listing for the 45-90 at all, only the 45/70 and 45-120 (only cast bullets, no 4759)
Pete
Last edited by PeteD; 01/15/14.
