Yeah, the .22 Magnum isn't going anywhere, though there's no doubt the .17 HMR has cut into its market. But the .22 Magnum ise very useful for some tasks the .17 HMR just doesn't do as well. It's much like the difference between the .25-06 and .30-06: Same case but with a vast difference in possible bullet weights and field performance.
But the .17 HMR did provide an entirely different kind of performance than the .22 Magnum. Probably some 5mm Remington fans will argue "their" round did it earlier, but the original Remington 5mm factory load wasn't much different than the .22 Magnum's, which is why the 5mm went tits-up.
Most of the cartridges mentioned so far simply reproduce the ballistics of much older cartridges, but in a shorter package to fit in shorter magazines. The .300 WSM doesn't do anything the .300 H&H won't do, and the same applies to the 6.5 Creedmoor and .260 Remington when comparing them to the 6.5x55, or 7mm-08 and 7x57. That's not revolutionary, just a realistic rearrangement of case shape to conform to modern bolt action magazines.
The .300 Blackout is pretty much exactly the .300 Whisper, which J.D. Jones developed more than 20 years ago. The .204 is interesting, but .20-caliber wildcats on the .223 case have been around much longer than 20 years.
John,
My thoughts are so many shooters who are now 17HMR owners would have not bought a 22 magnum. A entirely new market was created by a new magnum rimfire that utterly failed years earlier with Remingtons 5MM magnum. Marketing a better mouse trap and market timing with more ammo options and more importantly more rifle options led to the 17HMR success.
Doc
