This thread has been very interesting to read.
Thank you to all that have participated.
My brother is the rifle guru of the family. He likes his 220 Swift for ground hogs. He has .30-06's a plenty and 300 WinMags too. He loads for his son's .308 and shoots it as well.
My father gave me a Browning BAR .30-06 for my birthday a few years ago. It was bought used by a cousin, so no idea how many rounds through it. If I recall correctly it was made in 1994.
I will state the only advantage I have seen of having a rifle chambered in .30-06 instead of .308. I can find ammo!
Practical accuracy, the accuracy of in field hunting use, we can't tell the difference in any of the .30 calibers.
Now, talking about recoil... let me say this:
My .30-06 will knock the snot out of you.
I shot it 30 times one afternoon and remembered each shot for the next week every time I moved my right shoulder. No, I do not have any butt pad on it.
My brother usually shoots bolt actions for the known reasons of consistency. When he was helping me sight in the BAR with a new scope he commented how nice the rifle was. He had put in two off the shelf Hornady Superformance cartridges (150 grain) and one of his 110 grain hand loads that he had made specifically for hunting antelope. After he fired all three and we walked out to the target 100 yards away he was pleased to see a little Mickey Mouse pattern. "That's great, a rifle that isn't too sensitive to loads is a lucky find". He also commented, "That Superformance load kicks worse than my 300 WinMag, you need to get a butt pad."
My cousins shoot .243, and have never failed to take an Elk each year, and they drop them on the spot, with good shot placement. Point is, shoot what you like and the range of cartridges is quite large for hunting Elk down to Antelope.
I personally believe that anything that improves "placing" the cartridge in the chamber the same way every time, minimizing wiggle room, avoiding things that would alter the cartridge (like moving the bullet back) would be a good thing for precision.
Next, I believe anything that promotes consistency in the ignition would be good as well. If case shape helps, then case shape must be considered an important factor.
If there is a sweet spot in time and distance for when the powder is burned relative to the position of the bullet in the barrel then it has to be considered.
As this is a multivariate problem it is clear to me why so much work, study, and experimentation is done and why competing would be so very addicting to the inner engineer in all of us.
As for practical accuracy for hunting get a rifle you can afford in a cartridge that you can afford to shoot and actually find some ammo in that cartridge!
I don't know why I just typed all of that in, I don't think I added anything to the discussion, but it has been so fun to read I wanted to participate.