RE: .243 vs .257 vs .277 vs .284 vs .308 vs .338 vs .458
I agree with zrexpilot, Waaaaaay too many holes in your comparison.
How does one outkill another. Dead is dead right?????? Unless you are talking about different classes of animals such as deer vs. buffalo. Then you need to compare calibers or cartridges suitable for that class of animal.
Effective killing power for which animals.
There isn't a cartridge or caliber made that is "drop them in their tracks dead" reliable. Bullet placement and bullet constructioncombined are the only things that can be considered "drop them in their tracks dead" reliable.
.308 caliber is best for who and in what cartridge. Is the 300 Remington ultra mag (it is a .308 caliber) better for a 9 year old girl than the .243 Winchester when hunting deer?
Go with a 300 savage? Well that one is certainly waaaaaaaay down on the list of available ammunition. Then the 30-30 is limited in range compared to the 7mm-08 and depending on where you live could very well be way down on the list of available ammunition.