I have often wondered about loading the 9.3x74 with black powder.
it is impossible to give a load , as different lots of black powder can vary in density.
here is how you do it.
you need to establish where the base of the bullet is in the neck.
ideally there is room in the neck to have a thin (card or cooking greaseproof paper) wad under the bullet, a grease wad, and another wad under the grease wad on top of the powder
the starting charge should be up to the bottom wad.
increasing the charge 1 gn at a time will require compressing the powder to get the same column height.
this should be done with a compression die not the bullet, as the bullet might be deformed.
at some stage of compression you will find best accuracy.
also compression will mostly improve powder burn, meaning you will get more shots without cleaning before you cannot chamber a round.
composition of the grease wad is important.
most of the lubes you buy are for grease grooves, and as wads are a little too hard.
when yo chamber a round into a dirty barrel, blowing into the chambers will help soften the fouling.
you might find pistol primers give better ignition than rifle primers, but not necessarily.
another way to make grease wads is to soak the grease into felt.
bruce.