A regular 357 Magnum load out of a short barrel is going to generate a higher velocity than a regular 38 Special or 38 Special +P load. See Stephen Camp's article
on this topic.
Now, if you're getting 1150 FPS out of a 125 grain JHP, then you have just duplicated what a Glock 19 does with Speer Gold Dot 124 grain JHP. If you break 1200, now you're seeing some improvement.