The problem with reduced loads of H-110 and W296 is a phenomenon called detonation. It is when the powder doesn't ignite in a normal way, but in some abnormal way, and this causes paradoxically high, VERY high pressures. Which can blow up guns.
Factors favoring detonation are: low loading density, reduced loads, use of regular primers where magnum primers are called for, and possibly light crimp.
Win makes Hodgdon powders, BTW, and the burning rates of H-110 and W296 are very close. I spoke to a technician at Hodgdon a while ago, and he stated that the detonation phenomenon was nearly impossible to duplicate in the laboratory, but it did occur, and he had personally seen it.
Win DOES list 'reduced' loads for W296 in their latest loading manual, but only for one cartridge, the .454 Casull, and the 'reduced' loads generate 38,000-40,000psi. The full loads generate 50,000psi!
I would follow the advice of Mr. Garret. He makes the world's best .44 Mag ammo. Walt