My dear friend PontonOut of curiosity , CBH Australia ... How come the .30-06 Springfield calibre never quite caught on , with you Australian gentle men ?
When I visited Australia in 1979 to hunt my Kangaroo and some Magpie Geese ...
The .308 Winchester and .30-30 Winchester appeared to have a national following in Victoria , Tasmania and New South Wales .
The 06 never really caught on in Australia because we had the 303 British as a service round and for use as a full bore long range target round.
When we transitioned to the 7.62x51 in 1957 it was just a natural progression for Australian hunters to do the same and go for the 308. The same happened with the 223.
Both were cheaper and easier to get than other rounds.
Australian hunters didn't really need anything bigger apart from for buffalo hunting.
In the US they had the good old 06 from the early 1900s and it became a favorite with American hunters.
Hunters in OZ when I was growing up in in the 50s and 70s thought the 06 was just to powerful to warrant it's used. There were a lot of people also that thought the 303 was to much gun so necked it down to 22,24,25,270 cals to make it a better hunting round. In the early 60s importing of other calibers was starting to become more common and the older cartridges fell by the wayside.
I hope this helps you my friend.