Let's face it - MLs are obsolete. You might as well plan to hand load cartridges for your firearm. You will be particularly limited as to proppelants and primers, but you have the same constraints with muzzle loads (percussion caps or even more finicky flints).
Hand loading, especially straight wall cartridges like 38 Special or 45-70 is quite straightforward, and not all that difficult for something like a 30-06 (if fired in the same weapon).

In effect, you just do your loading beforehand....