RonH;
The second edition of the NRA "Reloading" manual pressure tested Keith's loads. The old load (18.5 grs of 2400 in balloon head cases that had more capacity than modern solid head cases ran about 20,000 psi with the Lyman 429421 bullet. 17.5 grs with the Lyman 429244 (gas check bullet) in solid head cases ran 22,000 psi (greater pressure with the solid head cases in spite of one grain LESS powder).
Using the new solid head cases with 17.5 grs is within pressure limits of the "N" frame smith in .44 Special caliber. However, I treasure my .44 Special Smith's and would not recommend these heavy loads for continuous use. Using them just for hunting should work well.
One thing that concerns me is that the "NEW" Alliant 2400 is reportedly "faster" than the older issues of powder. I, personally, would chronograph the loads (old powder against new) and not exceed the velocity reached by the old powder. That is not the same as a pressure gun but will hopefully keep a feller or gal out of trouble.
I have run some of the old Keith loads without problems but since I have several .44 magnums, that is what I use for deer. Again, my .44 Specials are quite happy with the Skeeter load.
Dale53