Thanks Garvin

That is the picture I saw, and thought I would find the hidden date, but nothing. It doesn't look polished out and reblued either. I know from searching that the mid 30's guns had the different trigger, and hence different end cap. Does the end cap unscrew on yours? Crono results were very consistent at 515 for hobbies and 460 for superdomes. I think this is about right. I would like to get inside sometime soon to check the piston seal condition, so as not to damage the mounting screws by shooting if it is going bad.
Thanks