dating a model 11

[RickT]

I have a model 11 12 gauge shotgun and would like to know what year it was made. Serial number 801571. On the left side of the barrel it is stamped FULL and has a screw on choke that says POWER PAC. It also has some small letters that look like KTT on the left side of the barrel. I looked this up and the KTT would seem to indicate the shotgun was produced in May of 1948 but they stopped producing them in 1945. I also looked in the factory records serial number section and could find no matching number for a model 11. Anyone who can shed some light on this would be appreciated,