I have loaded many thousands of rounds of .44 mag. for both pistol and rifle. I believe if you want to use a rifle, use a rifle round. There is minimal gain going from a pistol to a rifle if using a pistol round.
You can't change a pistol round into a rifle round by different loading. Just use proven loads and go with it.
p.s. If you are using a Marlin you have to stick with slightly below max. loads anyhow. DAMHIK
