Perhaps we need to look at who and why people collect things and how it pertains to doubles as a group. Modern guns are more efficient at killing game so collectors are going away from efficient. For example a 3 1/2" auto loader can kill three birds in a short time frame. Synthetic composite stocks, camo finish, massive payload, interchangeable choke tubes for perfect pattern choice to game, light gathering sights all are more efficient at their task. Doubles are quaint as my mother use to call them, quaint.
I think we collect as a way to relive a time period in the past. Model T prices are down because the number of people who grew up riding in them, as a small boy, are down as well. They are in their 80's and 90's if still alive, so most of them do not even drive much if any anymore. The market is down because the number of buyer is dying out and the connection as well.
WWII stuff, for all but the best stuff, is about to hit the same problem but in 20-30 years. WWII servicemen are all in their 80's and are interested in getting rid of stuff not buying. The next generation is picking up the slack for now but they are in their 50's and 60's so their buying period is coming to an end.
Most people collect stuff from their youth or perhaps from their parents youth. Not much interest in going much further back in time except in some major event time frame. Civil war stuff will always have a following but not so much with WWI. WWII but not Korea or even to a large extent Vietnam.
High grade stuff will always have a market but I see the market for low end stuff being soft in the future. That is why I have real estate and stocks instead of guns as in investment. And even then I buy only what I understand not what the talking heads are talking up. The Best stock tip I ever got was that almost every stock tip you ever get will be wrong. People will talk up what they are dumping to keep the price up not because they are giving you free tips to get rich.
