I believe that what you are going to find is that the Model .270 Winchester Short Magnum is a dud.
Winchester - in their haste to come out with newer versions of the wheel did not do their homework..
The bullet might fly faster and farther, but the ammo is so expensive that most people will not waste their hard earned greenbacks to buy one.
In time that ammo is going to get harder to come by and more expensive.
In the very near future, nobody is going to manufacture a modern rifle in that particular caliber / WSM and it will become obsolete. For the most part, Winchester is out of buisness and Browning is so over priced that it is just a matter of time.
A good example of some other caliber's that had the same problem is the 22 Jet, 22 rocket, 7 mm Express Remington - which later changed it's name to .280 Remington.
My dad said that the 7mm didn't do well because they already had a .270 Winchester and there was not a lot to be gained by jumping a couple of thousandths bigger in diameter. Plus the veterans of WW I and WW II had hard feelings against the Germans and the Japanese and didn't like anything that had a MM after it because they associated it with the war and the junk rifles that the Japanese carried.
Wykopedia
History
Having been released 32 years after the.270 Winchester and having no particular advantage over its predecessor, it had somewhat unspectacular sales; Remington renamed the cartridge in 1979, calling it the 7 mm Express in an attempt to increase sales. This resulted in people confusing it with the 7 mm Remington Magnum and Remington eventually changed the name back to .280 in 1981.
The .280 Remington is capable of developing energy nearly equal to the .30-06 Springfield, but with lighter bullets having a better ballistic coefficient. Thus, the .280 has a better trajectory and retains more energy downrange. However, the .30-06 produces more energy than the .280 with bullets heavier than 180 grains. The .280 is suitable for hunting any game in North America.
The .280 Remington is not popular in Europe, where it competes with the 7 x 64 Brenneke, to which has almost identical ballistics . When compared to the .280 Remington the 7 x 64 has a slightly higher maximum allowed chamber pressure and as an European 7 mm cartridge has a slightly larger bore. European 7 mm cartridges all have 7.24 mm (0.285 in) grooves Ø diameter. American 7 mm cartridges have 7.21 mm (0.284 in) grooves Ø.
In 20 years, Wykopedia will have asimilarr entry for the .270 WSM