The 9x23 Winchester is already the ballistic duplicate of the .357 Magnum, FWIW.
I don't know if the following is true, but it is worth thinking about. I'd like to know if it is true.
Performance and usage
The 9x25mm Dillon was a success in that there was a noticeable reduction in felt recoil, especially compared with comparable 38 Super IPSC Open guns. When fired the gun recoiled almost straight back into the shooter's hand rather than up and back. This resulted in competitors being able to fire their second shot more accurately in less time which increased their score. Another advantage was that when loaded to the old USPSA 175 Major power factor, the 9x25mm Dillon case didn't show any signs of excess pressure, as the internal volume of the donor 10mm case could easily handle pressures that were generated, whereas some 38 Super rounds loaded for the 175 Major power factor showed excessive pressure signs.
There were, however, some drawbacks to the cartridge. First was that since it was based on the 10 mm case, magazine capacity in a double-column 1911 magazine (such as a Strayer-Voigt or STI) was reduced by 2-4 rounds compared to a similar gun chambered in 38 Super or 9x21mm. Second was that some users of the 9x25mm Dillon were experiencing parts breakage on their guns at a much higher rate than a similar 38 Super - cracks in the compensator and slide and broken scopes.
But the biggest drawback to the cartridge, and the one that largely contributed to it falling out of favor was the enormous shock wave that was produced when the cartridge was fired. When firing the gun, the shooter could actually feel the impulse hit their face and travel up their arm. After a while, some people began to experience tendinitis in their wrists and other soreness in their wrists and arms. For a lot of people the trade-off from reduced felt recoil and a quicker second shot wasn't worth the potential damage that could be caused to their hearing and wrists.
http://en.wikipedia.org/wiki/9x25_Dillon
