I am looking at a Smith and Wesson Revolver manual revised 6/93 which lists a small frame ammunition chart which approves +P ammo only in the Model 60-4 with full underlug, the 60-7 and 60-8, the Model 640 (.38 version), and the Model 649-2. The models 36, 37, 38, 42, 442, 49, and model 60 dashes 1-4 were not factory-approved for +P. Clearly, a couple of years later when Smith and Wesson "magnumized" and slightly enlarged the J-frame, they approved +P for all small framed revolvers, but the above was their recommendations for older-styled J-frame revolvers. I ain't saying the guns won't take it, just that S&W wasn't approving of it.