I've actually tested a 125 gn HDY HP over 21.5 grains of H110. Pistol used was my S&W model 620 and the produced velocity was 1410 fps, just a tad short. The muzzle blast produced was a close rival to a 500 Magnum and according to witnesses the flash was 20 feet long. In addition the flash ring from the B/C gap totally obscured the target. IMO this is NOT a practical load for for a handgun but would be a very flat shooting load for a Rifle. I also expect that in a 20 inch Short Rifle it would probably break 2200 fps.

IMO H110 is a fantastic powder for Rifle loads but it's a poor choice for 357 Magnum Handgun loads. It's just too slow burning and needs a longer barrel to be really efficient. For my handgun I use Accurate #5 for the Magnum "light" and Accurate # 9 for more serious loads.

I'll also note that my primary arm for home defense is a 12 gage shotgun. Because it is vastly more devastating than any handgun.