I just picked this beauty up monday and am just now getting to look her over, Wow! Old school S&W craftsmanship just oozes out of this thing! This is my second foray into j-frames, first one being an m60-7 ( another fine piece ). I noticed that while they both seem identical by most outward appearances,  there are a couple small variations: the 649 has 2 small pins protruding from inside the cylinder that correspond to 2 holes in the star extractor while the 60 lacks that feature.
The grips on the 649 are fantastic! I would like to get a matching pair for the 60, or maybe another set of Uncle Mikes...anyway,  the grips are wood but I don't think they are laminate.  It's a very tight grain and it resembles a tiger eye stone when you shine light and move it around, beautiful wood. There is light checkering with a fleur de lis< spelling > on each end of the grips and a J milled inside one of the grips. That's it as far as markings go for the grips.
Now to date this fine piece of craftsmanship: the serial # BBN73XX.
My 60 is BRL55XX and when I called S&W I think they dated it at around '94.
Well, that's it guys. Hope y'all can help me out. And you guys aren't kidding about these beauties multiplying like rabbits! I really dig jframes more than any other S&W style, at least for now. It's funny because when I first saw the " humpback " pistol as a kid I thought it was ugly as hell! oh well, opinions and taste change with age they say, maybe the other frame styles will call to me soon...
Thanks a bunch guys!
                                        Ray IV