Black powder cartridges of the second half of the 19th century could only produce more "power" by using large bore sizes and heavy bullets, since there was a limit of 1400 fps or so on velocities that could be produced by BP.
Most people do not load their modern muzzle loaders with the same kind of projectiles used by BP cartridges Back in the Day. Today's muzzle loader bullets are usually less than full bore size due to being contained in a sabot, and are basically nothing more than glorified pistol bullets with weights fairly light for their caliber.
Of course, these loads are very effective for the type of hunting we do today and many of today's bullet designs perform out of proportion to their weight by traditional standards, and modern BP substitutes give velocities quite a bit higher than BP can produce.
BP cartridges of 125 years ago used full bore size lead bullets in true rifle weight. The .50/70 used a 450 gr. bullet and the .45/70 used 400 to 500 gr. bullets. These bullets at BP velocities gave excellent penetration on large game such as bison .
If you loaded your .45 caliber modern muzzle loader with a heavy lead bullet such as a No Excuses 460 gr. with 70 grs. of FFG BP, you would have the equivalent of an original .45/70 load and it would work just as well on bison today as a Trapdoor Springfield would have in 1876.
Such a load would be considered "moderate" today, compared to, say, a .375 H&H by most hunters, but the bison that was hit with it would still be just as impressed in 2014 as it would have been in the 1870's.
Last edited by wildhobbybobby; 08/13/14.
