I have a S&W mod. 29-3 serial. 325xx with a non-fluted cylinder and a 6in.full underlug barrell (it actually measures 5 3/4 in. ). It also has a 4 position front sight. I bought it in the early eightys and was told at that time it was of a limited production . I have never seen another one like it. I would apperciate any information on this model. thank you kbk