Bought this at gun show, BROWNING PATENT 12 GA PROOF TESTED on barrel with a O with 6 inside it with FULL under it, also angled crescent with o in it on left lower side behind mag tube. It has a cowboy on horse back and RANGER on upper left side. Serial number behind trigger guard is 97xxx with the 9 slightly lower than the 7xxx. There are no other markings on gun. Does anyone know what I have and a date of manufacture? THANKS