No clue if this is going to help you because i don't know much about it but i did a google search and found this.The pics have close ups of the serial #
No clue if this is going to help you because i don't know much about it but i did a google search and found this.The pics have close ups of the serial #
JonJ, M12's have the serial number on the bottom of the receiver right where you would grab it to carry it around. The barrel/magazine assembly has a number right next to the number on the receiver. The numbers should be the same but the type could be different. If you find the serial number let me know I'll look it up in Dave Riffles book and give you the date of manufacture, etc. John