According to my Smith&Wesson hand guns book by Roy C. McHenry and Walter F. Roper that is indeed a perfected model .38 S. & W. top break and side lock revolver. Manufactured from 1909 to 1920. Hope that helps ya out.
"I know what you're thinking. "Did he fire six shots or only five?" Well, to tell you the truth, in all this excitement I kind of lost track myself. But being as this is a .44 Magnum, the most powerful handgun in the world, and would blow your head clean off!" - Dirty Harry