More trouble than it's worth. I had a 338 Scovill (a 338-06 Improved modeled around a 9.3x62 case) built on a M70 one time. I did not get enough additional velocity out of it over a 338-06 to make it worth the hassle in case forming.
Improved cartridges are a nice idea, but after fooling with a couple, if I wanted more punch than a 338-06, I'd go to another cartridge - 338WinMag, 9.3x62, whatever hits your fancy. Spend more time shooting & less time case forming.
Only my thoughts, but they're yours FWIW
