A circa 1890 S&W single action, 2nd model, 5 shot revolver with spur trigger has been passed down through the family for generations. I've begun reading up on it, thanks in large part to this forum and a couple of e-books, but I would like to narrow down the possible causes of the hammer not catching when cocked. (The pistol isn't pretty, but mechanically seems OK except for the failure to remain cocked.) I do have instructions for disassembling it, and have detailed illustrations of earlier single action spur trigger pistols, but don't know where to start looking for the source of the problem. Since I'm a newbie to this forum, any help would be greatly appreciated. Thanks!