"...whats the realy story on the 44 mag and this data?"
The guys who do the books know what they're doing and that includes the pressure system they're using. Stick to book data, especially for handguns, and you'll be okay. I think. Occasionally anyway, ?? I mean, it's scientific but reloading really an art, not a science so pay attention to pressure indicators no matter what the books say. Most certain "pressure" indicator in large revlovers is sticky extraction, forget the signs that work for rifles or you'll blow your revolver from together.