Brad,

The "C" is not part of the serial number. It was used to identify design changes that were made to the gun, and which parts were needed during the assembly process. The very early Model 1897s did not have a letter stamped above the serial number, then in the 48,000 serial range, the "C" was added. The "C" was replaced with a "D" very near serial number 249,000, and the "E" series began near serial number 420,000.

Serial 236777 was manufactured in February of 1904.

Bert