[Nyles]

Actually the Colt New Service WAS available in both the .38-40 and .38 Special. That said, without have seen the show, it sounds like you're talking about a commercial model 1889 Navy, available in .38 Long Colt and .41 Colt which would become the US Army M1892. Also could be the New Army and Navy from 1892.

And the idea that any of these were the first successful double-action revolver is downright insulting. In terms of revolver design quite frankly the US was years behind Europe for most of the second half of 19th century. The first successful double action was the Beaumont Adams 1855. Hell the Deane & Adams was a successful DAO in 1851. Hell, the first successful American double-action was the Smith & Wesson Frontier 1884.