Jason,
There should be some roman numerals stamped on the barrel flats, those are the date codes for when your gun was made. The numbers start with I for 1945, the year the war ended, and progress one at a time.II=1946,III=1947, ect. In 1974 they stopped the roman numerals with XXX.1975 =AA,76=AB,etc. If you send me the number or letter stamps, I will tell you when the gun was made. If you send me your email and a request, I'll mail you a copy of the date code sheet.