I read the other day that you can shoot a 45-70 in a 45-90 Sharps does anyone out there know this to be true or not..............and does anyone know of a starting load with smokeless power and the likes of a 300 gr Hornady for the 45-90 Sharps

Short Range

IMO you could easily stick 45 grs of h4198 in there,cause all that freebore is going to lower pressure in a big way..I;d start about there,and maybe work up,but not much..As you well know when criss crossing cartridge length and in BP guns pressure signs are hard to read...I'd say when you get that 300 grainer coming out in the low 1900's fps thats the stopper