You'll be using one of the fastest pistol powders on the market in a large bore, large case, high-pressure magnum round. It can be done, but you should know going in what you are getting with a load like this.
Using a FAST powder in something like .44 Mag gives you:
--less bullet velocity than you'd expect out of a .44 Magnum load
--ALL the same maximum pressure
You have much, much more risk of an unintended overload when using a fast powder in this round.
Yes, you can do it. The best use of a FAST powder in a round like this is when you wish to make a light load...one that doesn't run a "magnum" velocity and doesn't give the full, heavy recoil of a proper round.
If you have any hopes of making full-power .44 Magnum, you need to find a better powder for the job. If you
attempt to run HP-38 hot in .44 Mag, you can blow up a handgun easily.
For published load data, look it up at Hodgdon's fine resource:
http://data.hodgdon.com/main_menu.asp