/ Back Browning A-500 History The A-500R shotgun was introduced in 1987 and discontinued in 1993. It was a short recoil operated model. The A-500G shotgun was introduced in 1990 and discontinued in 1993. This was a gas-operated model.   Date Historic Information Serial Number Info 1987-1993 In 1976 Browning standardized its serial number identification which it followed until 1998.   1. A-500R Type     A-500G Type 751=A-500R 351=A-500G 2. Date of Manufacture is a two digit code Z=1 Y=2 X=3 W=4 V=5 T=6 R=7 P=8 N=9 M=0 3. Serial Number beginning with 01001 at the start of each year.   A-500 R Serial Number Example: 751PR01001 This would be an A-500R shotgun, manufactured in 1987 with the serial number 01001 A-500G Serial Number Example: 351NM01001 This would be an A-500G shotgun, manufactured in 1990 with the serial number 01001