Like Canvasback, I have a complete set from the third year onwards and a few issues from the first year. DGJ will remain a good reference work for anyone interested in fine guns, and American double guns in particular.
I can't help but stop and think about periodicals that pertain to our shared interests. A number of magazines have come and gone, though few have touched on fine guns and gunmaking. It just goes to show that it is a niche subject, with fervent but limited appeal. As businesses, publishers must cater to a wide public to survive, and the DGJ audience has been ageing and getting smaller, I suppose. To remain viable, a magazine has to move with the times, and apparently, there is more interest in anything with plastic stocks, picatinny rails, camo, 3 1/2" chambers, mag extensions, and warranties to cover the shoddy parts that inevitably break in the first week of use. Over the years, I've subscribed to DGJ, Shooting Sportsman, and in Europe, to Classic Arms & Militaria, Guns Review, Sporting Gun, and Shooting Times. My interest in these was linked to specific writers and columnists, and when these left or passed on, my subscriptions ended, with the exception of the DGJ. The subject matter that evolved with the times in the other publications did not suit my interests. Like others have said, in recent years, the DGJ subject matter was a bit hit or miss, though I was happy to maintain my subscription for the occasional gem of an article (and, like Ashcroft, I recently extended my subscription).
I suppose the overall change in our society with respect to information availability is a factor. With social media, it is difficult to keep anyone's attention span beyond a few seconds and a click of the 'like' icon. It used to be that specialist knowledge was found in books, and keeping a library was part of a shooter's hobby. It appears that for many, a Google search now satisfies most curiosity. Like with the DGJ, I expect the market for new books on gunmaking and gunmakers is also diminishing. The amount of work and research required to write on the subject is rather daunting, even for a magazine piece. In line with the paucity of new books, I don't see many emerging writers engaging readers with their prose. Again, the social media format works against this; a captionless picture will generate as much if not more interest as a carefully researched and written text, so why would anyone bother? Am I just getting crotchety in my old age, or am I seeing a gradual lack of curiosity within the gun community? Is thirst for knowledge a generational thing, or has our addiction to the Internet changed how we interact with and value information? Or is it just that no one bothers with books anymore, as so much is found online with a click? I'm sure someone is studying this somewhere.
On the subject of periodicals, I'm currently going through past issues of The Field (aka Field: The Country Gentleman's Newspaper) for my research. It is still in print (and online) as a monthly magazine, but in its early years, it was a weekly newspaper (each issue was 16-32 pages), first appearing in January 1853. In the 169 years and 7 months it has been in print, there have only been 14 editors. Most interesting to me was that from 1857–1888 John Henry Walsh was the second editor, an author who wrote books under the pseudonym 'Stonehenge' and who had a particular interest in the new breech-loader. In The Field letters column raged the flame wars between fanboys and detractors, each side taunting and trolling the other, documenting the would-be influencers and the butt-hurt. Good reading, by Jove! This was the social media of the Victorian era; I suppose things don't change much after all.
Fun Fact: The Shooting Times magazine in the UK is a weekly publication which started in September 1882, and has never missed an issue (despite several world wars and other annoyances).