Looking at a 338 RPM cartridge, it reminds me of a 9.3x62 necked down to 338, ha ala the 338 Scovil! Not bad company to be in.
The 338RPM has almost exactly the same case capacity as the 338WinMag, so it's a good bit more potent than the 338-06 (or your very similar 338x62).
