I strongly suggest a trip through a few different reloading manuals.
Each different powder formulation delivers a different bulk-to-burn-rate property.
Thus, the powder that would deliver a practical set of loads for the 9mm would be inappropriate for practical loads for the .44 Magnum. The larger case requires a different propellant formula from that of the smaller, to achieve proper efficiency.
It is probably possible to use only one powder for all three calibers, but then other compromises would have to be made, and efficiency (and practicality) would suffer.