I have a CETME 7.62X51 rifle from Century Arms that I purchased several years ago. This is a look alike of the Heckler & Koch HK91. This rifle has the wood furniture with a leather sling. I am trying to date this rifle by serial number. I have not been able to find any source thru which I can do this so far. I have determined that it was made in St. Albans Vermont and that it is a cast receiver as opposed to a stamped receiver. The serial number of the gun is stamped on the top of the receiver and is C02457. So does anyone know, by that serial number, how to date this rifle? Are there any other identifiers that would help to determine the date of manufacture?