Your load of H110/296 seems a touch low to me. I have used 296 for heavy bear stopping loads with 265 gr hard cast bullets, with 20.3 gr. It works fine in my Model 57s, certainly not too hot. H110/296 (same powder) does not like reduced charges.
I’ve been loading and shooting this cartridge for over 40 years, and my all time favorite powder is 2400 for 210 and 215 grain bullets. If you have some, you may want to try it.
I got away from those powders and went with accurate #9. Handles reduced loads very well also goes full bore with ease. 210-215 same powder. Although the old standbys of Red Dot and Unique also work very well.
