It used to be told around campfires, back when the brontosaurii roared just outside the flickering light from the campfire, that certain individuals would scratch a name on the cartridge case, thus indicating that the bullet was reserved for that named person. It was usually the name of an enemy.
Then soldiers took to engraving their name on a cartridge and wearing it on a string around their neck in the belief that since they held captive the one "with their name on it" they would not be shot - or at least not killed. That worked well for a short while, until it was discovered that it was not "the bullet with your name on it" so much as the one engraved "to whom it may concern" that was likely to kill you.
So, we see that down through history the notion of marking bullet cases has been pretty much an abject failure.
stay safe.