Good morning
Looking at my old Lyman Cast book 1973 it shows the 38 S&W which is right at the same length of .775 loaded with a 158 grain with a starting load of 3.2 grains Unique (my favorite powder) . Max load listed is 3.7 as fired in a S&W M 33. Me I would start out at 2.8 grains and increase at .1 increments.
A model 10 should be able to take that starting load. Be sure to check the cylinder throats as they may be large. I personally like a snug throat fit and use .001 + over throat diameter depending on the revolver. SOFT cast bullets would be better in this little case.