Some years ago there was a participant here who lived in Mexico and spoke about that .38 Special limitation. I believe that he said was that the only thing the Mexican authorities checked for was that the revolver barrel was caliber stamped as .38 Special or smaller. He also said that it was not unusual that Mexican shooters handloaded .38 Special cases up to .357 levels. Of course, it is well known that there is a complete absence of any illegal firearms in Mexico.