I don't think the '06 came from the 9.3x62.
I think rather that both the Americans and Otto Bock were looking at the longest possible cartridge which could fit in a standard Mauser action and ended up with cases that were almost identical.
Hardly suprising.
And the 9.3 has it over the 35 Whelen because it has a shorter neck and slightly more powder space.
The Whelen's shortcomings as an African cartridge stem from the fact it was designed with Nth America in mind, much as American hunters probably feel the heavy 9.3mm bullets limit the '62.
As to the comments on the heavier 338 pills, especially the 300 grainers, remember that bullets that heavy are designed for long range shooting using rounds like 338 Win, 338 RUM, 340 Wby and 338 Lapua.
Even if they are hunting bullet they are not likely to expand as happily at the velocities the 338-06 can push them.
The 9.3x62 OTOH is the most prevalent cartridge in .366" cal and so bullets in this cal are designed with its ballistics in mind.
