WHAT DOES 38 CALIBER BULLETS MEAN?

The flat meplats (frontal region) of SWCs and WFNs are vastly excellent to spherical-nosed projectiles for transferring Electrical power. The three hundreds quoted are +P masses but exhibit no pressure indications and don’t direct the bores of my revolvers.I just purchased some 158 gr SWC bullets which can be pure lead. How am i able to notify Wh