Engraving must be at least .003 deep and in plain sight, can be marked on barrel OR receiver, probably best if receiver. HKs? Say mag well, top of receiver, or right in front of recoil plate, you can no longer mark in hidden area.
Engraved info can be abbreviated, your initials, city, state, zip, just some way for LE/ATF to ID rightful owner should it be lost/stolen.
Engraved info can be abbreviated, your initials, city, state, zip, just some way for LE/ATF to ID rightful owner should it be lost/stolen.