Winchester introduced the 300 WSM 1st quickly followed by the 270 WSM. The 7mm WSM was supposed to be introduced shortly after, but it was discovered that a 270 WSM would chamber and fire in 7mm rifles. Since the 270 was already in stores the 7mm version was held back until a slight redesign could be made to prevent this. By the time the 7mm got on the market most of the demand was met. The 7mm WSM is the one most likely to die off. Which is too bad, it may well be the best one.
I don't know how many would like a light magnum rifle. easy to carry hard to shoot
All the Winchester WSM's have 24" barrels and they actually do quite well from 22" barrels. The 300 WSM was designed 1st. It's sole purpose was to split the difference between 30-06 and 300 WM and do it in lighter mountain weight rifles while keeping recoil manageable. Any of them, in the right rifle, would be a darn good long range mountain gun. But part of the problem is that most manufacturers, and hunters never recognized the purpose. Other than Kimber they keep trying to compete head to head with traditional belted magnums. Most hunters see the WSM's being 100fps slower than the long action belted magnums and ask why?
I realize I'm talking 300 WSM, because that is what I have, but when you compare the 7mm WSM to 7mm RM or 270 to 270 WBY MAG the same principles apply. My 7.5 lb. 30-06 shoots 180's at 2800 fps with 22 ft lbs recoil. My 300 WSM shoots 180's at 2950 fp with 26 ft lbs recoil. A 300 WM shooting 180's at 3050 fps would have 30 ft lbs recoil if all 3 are the same weight. I simply don't notice the 4 ft lbs recoil difference between 30-06 and 300 WSM. But I do notice the 8 ft lbs difference between 30-06 and 300 WM.
I honestly have no need for it, but I ran across this 300WSM rifle and scope for $400 several years ago. It was in the factory tupperware stock and Bubba the gunsmith ruined the stock trying to add a recoil pad. That is why it was so cheap. I bought a used McMillan Edge stock for it a couple of years later. I have about $800 total in everything you see here. It is more rifle than I need, but I just like it and the caliber. Would probably be just as happy if it were 7mm WSM.
If more manufacturers would recognize that the WSM's aren't meant to compete with long action magnums and start offering them in lighter rifles like this I think they'd sell more.