The reason the 338 Rum is shorter is so that existing .338 bullets could be seated in the case and still maintain the same cartridge OAL. Designing a cartridge that can't fit into the magazine of the rifle it will be chambered in would be by all means "stupid". Now i agree with the sentiment, that it would be better if they had made it the same as all the other RUMs, but they will take the easy road every time when it comes to spending money. It was either redesign bullets to fit in the long case or simply shorten the (still in design) 338rum. One way would have cost them a great deal of money, the other cost them nothing! Besides, they made that line of cartridges to sell rifles, not to please handloaders.