As reagrds your questions 1.All vintage centre seconds are hand wound. I know of no auto SC 2. I think there are some other calibres beside the 27 SC but am not sure. This calibre is certainly the most common 3.. Not water resistant. Most vintage pieces a
27SC is NOT autowind. there are a number of models which carries this particular movement. the most famous being ref 570. but overall, i like 27sc center seconds movement, not easy to come by. ref 565, 570, 1491, 2457, 2555, 3504, 3411, 2460, 2533, 2508,
While my beloved 5056 is getting a spring cleaning and adjustment at Patek NYC, under the capable supervision of David Jarrett, I switched to an oldie but goodie: This is a 1952 Patek Philippe Ref 2466, with the 27SC movement (see example below). The last