The .450 Marlin basically has the power of the smaller manufacturer's (Cor-Bon, Buff Bore) .45-70 loads. The raison d'etre for the 450 is to provide a gun that will handle the tope end of the .45-70 scheme, yet have a cartridge that can't load into older .45-70s (like trapdoors, foreign replicas, etc) and blow them up. Ballistically, it's identical to the uploaded .45-70. The thing that hurts the 450 right now is a lack of diversity in its factory ammunition selection, and subsequent higher prices than comparable .45-70 loads.