This subject came up a couple of blogs ago, and it’s a good question. There’s no doubt that we’re overwhelmed with cartridges, and that the struggle for survival is much fiercer than it was a few years ago, but some — some — of the shortfats are excellent rounds that will have long and happy lives.
The most likely to thrive long-term is the .300 WSM, which is profiting from our deep love of anything in .30 caliber. It is an excellent cartridge that is the ballistic duplicate of the .300 Win Mag. It’s very popular among builders of custom rifles, which seems the surest gauge of any cartridge’s success. When people of taste and culture glom onto something, it’s a good omen for the future.
Second on the likely-to-live list is the .270 WSM. Why this one is more popular than the 7mm WSM–which in theory should be a little more versatile–is known only to the shooting public. In any event, it’s about the same as the .270 Weatherby, and I like it better than the .300 WSM because it has a lot less kick.
The third may be a sleeper, and that is the .325 WSM, which is actually a short 8mm magnum. In the past, 8mms have not done well in the U.S. for reasons again known only to the shooting public, but this is a very good cartridge. It’s close to the .338 in power and may well have a career similar to that that of the .338, which has never topped any popularity charts, but has sold well for 50 years.
As for the rest? I am not optimistic.