I use a piece of brazing rod as a source for brass. Then shape it into a traditional flat graver. The brass won't cut the steel but easily cuts the gold.
If the serial # is between 2,700,000 and 5,024,957 you will need to use 1 of 3 different processes to get them black again. Years of manufacture are from 1964 till 1981, the receivers were cast. A brief history on the finishes can be found here...
Try keeping your graver to the negative area side of your design instead of centering your graver on the design, which will end up making your design smaller or narrower. I hope I have explained this correctly.
I'm slightly confused. Do you want some comments on the gun, "design possibility's", or are you venting some outrage against something we have little control of? If it's about the gun then I have no picture to go by.