FPS - Bounding box for the head and another for the body.

Im doing a first person shooter and i want to use a bounding box for the head and another for the body, but head and body are only one mesh.
How i do this?
I want to achieve this because i want to take, for exemple, 10 health when i hit in the body and 30 health when i hit the head.

Thanks in advance!

Off the top of my head you can do it either by seperating the models into componenets or you can use the results of your bullets to compare coordinates of the hit location and the player model location.