H110, according to everything I've read about it, & confirmed with my use of it is, it's at it's best at max loads with heavy for diameter bullets. Personally, I have little use for it otherwise.
Another powder might out perform H110 with a 150.
The different barrel lengths of the 2 revolvers not likely responsible for the big velocity diff. That is likely due to cylinder gap differences &/or bore smoothness. Cyl. gapiss a big player in revolver velocities.
I easily break the 1200 fps mark in a 4" with a 150 jacketed, using old, dirty, outdated 2400. Long live 2400!
