There are 3 common types of bullets... "Full metal jacketed" (FMJ), soft point (SP) and hollow point (HP).

FMJ's are also called armor pierceing, andgenerally have a core of steel to make them penetrate.

SP is a jacketed bullet with the lead core going all the way to the nose, or even sticking out exposed.

HP is the same as a SP except the lead core does NOT go all the way to the nose, and the jacket is open on the nose leaveing a hollow point...

DM