Couple years ago, R&D annouced they were introducing a cartridge conversion for the 1860 Colt. I sent in a 1860 frame and barrel assembly at that time for gated loading port and ejector work. Apparently they had problems with making the conversion units and called me right after they got mine. A later E-mail said it would be a few more months. I havn't heard anything about it since. They have my 1860 frame and bbl. assembly and repeated E-mails to have it returned go unanswered and I can't get a live person on the phone. Has anyone else had this kind of problem with them? I have 4 of their conversion units for 51's and 58's, that I got from Midway. I have no problems with their conversion units, just can't get a response from them on my problem..... Tenasaw