Best advice is choose a .432"-.433" cast bullet, they always work in the 44mag rifle, just depends on bore size when it comes to jacketed bullets, 44mag bores can vary quite a bit due to SAAMI rifle specs which are larger than pistol specs, tighter bores shoot .430" jacket just fine, barrels on the high side of the SAAMI tolerance not so much. You can slug the bore to find out whatcha have, see that info in the FAQs.
Tim