My simple observation is that handgun use, especially CCW, has created an entirely new group of users who have limited skills. They want a low recoil, easily carried handgun that for some needs to be stylish. I also think the importance of a large, slower bullet (45acp) being the best has changed because of the improvement in ammo. I could never get my wife interested in CCW until some of the new small autos and revolvers hit the market. We both feel comfortable with her using a .380 or even a .32 of some sort because ammo has improved for both. I personally still like the big slow stuff.
I think rifles are a different story. Sales drive the industry and I think some of the calibers that have been developed are to insure strong sales of new rifles. All of us who enjoy rifles are prone to buying a new one because of some new style or a "must have" caliber that will work for coyotes to hippos. When all is said and done, most of the common calibers like the .270, .308 and 30/06 are still great all around calibers. Some of the new WSM and similar new calibers are good and have allowed manufacturers to build shorter actions, shorter barrels and compact packages. Are they really better than the old standards? I don't think so, but some do. As for me, I'll stick to my trusty ole' .308. Dinosaurs like old things. So I guess to answer the question, yes, in rifles I think we have come full circle and many are re-discovering the old standard calibers.
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