The "DuMond" barrel is a very rare expensive Custom Target Barrel, they had to be custom ordered from the Du Mond Manufacturing Co. (1930-1940)
The only other reference to DU MOND barrels that I have seen was in 'Pistols, a Modern Encyclopedia' by Henry Stebbins. His co-author Bert Shay describes ordering a Dumond barrel and sights for a 1903 Colt .32 ACP in 1945. Mr Dumond was deceased by the time that book came out in 1961, so information on the Gorenet will be lacking.
Here is a video of a 1903 Colt w/ DuMond Barrel, found it interesting. "https://www.youtube.com/watch?v=0LnTxQg-5fM"
Mr. Dumond barrels were custom order only and I believe JACK O'CONNOR spoke of having a Springfield barreled with one. Elmer Keith mentioned liking them. Dumond died in 1943 or 1944 and the business was sold to someone, but they couldn't make a go of it. I have heard he made the majority of his barrels for pistols.