Can anyone tell me why the military issue 1911 .45 cal pistol has a 67 painted or inlaid on it behind the hammer? I heard it was because he was issued it while military police. Is this true. It has original finish. and have been told it was made where you can not wipe or remove the number 67 off even though i have not tried nor would i ruin any gun. Ty for any help. Have a nice day.