Articap has it right. The 45-70 bullets have a .458 diameter. The Orange sabots are made for .451 bullets for the 45 ACP, 45 Colt pistol bullets. I think you might have a hard time getting them down the barrel. If you want to use those bullets you might look into Paper Patching them. However Paper Patching usually involves all lead bullets. I'm assuming they are jacketed bullets.
Next best thing might be to swap them for some .018" lubed patches and .490" roundballs.