Just did a private party purchase of a like new Seies 80 Frame mated to a series 70 slide. It appears ro be in unfired condition. There is a machining mark approx 1 mm deep and about 1 cm long on the underside of the slide which is obviously a factory defect. Colt Customer Service encouraged me to send the slide in for examination but made it pretty clear that they would treat it as a cosmetic complaint. Any suggestions?