Sorry, I missed your post the first time around. I checked on the frame of the receiver and found a faint 16G, as you said. This tallys with the 1955 manufacture date. I also found 10 F U P stamped into the butt plate and butt stock. Any clue what that means? Thanks for the help.
When they stopped stamping SNs on the various subassemblies they went to a code system to keep them grouped. I don't think anyone knows what the codes really mean other than to provide a grouping.
