Most makers of revolvers no longer put the firing pin on the hammer. The older model Smith and Wessons had them there (my dad has one), but I don't think Colts revolver design ever did. The firing pin "floats" inside the guns housing. Think of a hammer hitting a nail hitting a board rather than a pick-ax hitting a board. As far a props go, it probably was altered so it could not shoot, but we would never see how it was altered by the prop master.