My 600 has no serial number, no "Model 600" & nothing stating its point of manufacture. The only thing it says is "CO2 SEMI-AUTOMATIC". I've got an oddball! Any info.
The only explanation I could think of, for that CR600 that the housing had been replaced by oem service parts that sometime don't have any serial number on them.
Yes my 600 has no serial number and has less information stamped into the frame than others I have seen in the US. Radical did confirm mine was the 1st variant with a non-piercing end-cap and the original box differs from the US boxes, so my guess is maybe the Canadian models were different than the US ones? Hard to know for sure due to the 40 years plus that it was sold.