I think Dick Rumbaugh may be right in referencing passage of the 1968 GCA. I can tell you with certainty that S&W (and Colt, Ruger and most other manufacturers) only sold directly to distributors (even if they required you to be a certified - insert brand name here - dealer), never directly to gun shops, in the early to mid-1970s, as I owned a gun shop back then, and would have dearly loved to be able to deal directly with the factory, instead of playing games with the distributors to get any decent (read saleable) guns! In fact, I had to use distributors throughout the U.S. in order to maintain a decent stock of S&W and Colt handguns. IIRC, Weatherby and Browning weres about the only manufacturers with which a gun shop could deal with directly, and Browning was a PITA. In fact, I threw the Browning rep out of my store after several unpleasant dealings with him (as well as their headquarters), and returned all my remaining Browning inventory. Roy Weatherby, on the other hand, was a true gentleman, and a friend, as well. He always bent over backwards to make sure everything could be done at his end to make things go well, even to the point of coming to my store (in Arizona) when we opened it to meet potential customers! Even after closing the store, he and I exchanged correspondence until he passed away. In any case, I digress, sorry. The switch to a strictly distributor based system may have coincided with the 1968 act, but was probably well along in the changeover process anyway, as it was, likely, becoming more and more inefficient for the factories to sell to thousands of small shops, with many small orders, by comparison to selling large orders to a (relatively) few large distributors. It also aided in streamlining production and forecasting production schedules for different models. A cost effective move for the manufacturer, not so great for the dealer.