If the mouthpiece is an original you have made a great purchase. The 80A I play is a 1941 model. According to what I have read you may wish to investigate if the mouthpiece you have is a short shank mouthpiece. I have hears but cannot confirm that short shank mouthpieces from earlier cornets may differ with regard to where the leadpipe and inner end of the mouthpiece converge. I do not have a Conn original mouthpiece but rather a more modern short shank mouthpiece and I do have intonation issues.