Well you know Remington doesn't know if that load will be used in an old trapdoor or in a Ruger #1 so it is a weak load and maybe not at the correct burn rate. WIth those cartridges( anyone step in here and correct me if I am wrong) crimp is extremely important ..it might be a fast burn powder and not all of it is being consumed. I'll have to note that the next time I shoot my 45/70 since I have always been a factory ammo shooter in that cartridge.