I'm fairly certain that the revolver you have described was made during 1906. I think they were still designed for BP at that point, but I am not certain. If the gun is in good repair then modern (smokeless) powder should be safe. We are talking about S&W 32 ammo not S&W 32 Long. But, as always you should have it checked out by someone who really knows old guns. My feeling has always been, why take a chance on an old gun. They're fun to look at etc, but shooting could be dangerous.