I swear to God I'm not.
I'm literally just 100% ignorant to all of this. While I'm posting I have videos up on youtube binge watching caliber comparisons but it's all Greek currently.
I do find the hostility here amusing though.
Yeah, kinda proving Darwin right just a little bit with all the poo flinging.
Then there are snots who say that .243 is fine for women and children but you need a .30-06 or even a .300 Win Mag.
Same mouth breathers who will tell you that the only hand gun and caliber you need to carry us a 1911 style in .45 ACP.
Where as, I like what my LTC instructor said.
"I have here a .45 ACP, a 9 mm, and a .380. Which one do you want me to shoot you with?"
Different calibers and styles of bullets have different uses.
So, the best way is to start with what the job is. Ringing steel or holes in paper at long distance? Then you need a sleek bullet that floats easily and disintegrates on impact. Lower recoil rifles also allow you to see the wind trace of the trajectory because the muzzle flip is minimal.
Want to hunt game animals? Check with state regs. For example, in Texas on public land, you rifle hunt deer with no smaller than a .243 Win. And many have used that. Eaching succeeding bullet and caliber size can, in general, do a little more.
It would seem that .308 (7.62 x 51 mm NATO) would be one of the worst performers. It is subject to wind influence. Doesn't have the powder capacity of a .30-06, the nearest comparable bullet.
Anyway, crunching numbers of the average factory ammo, such as I have, the Federal Fusion 165 gr in .308 drops below 2,000 fps a little past 300 yards. True, some bullets may petal fully below 2k fps but I want to idiot proof myself. But if you have hunting situations that are always that close, go ahead. If you need some more distance, you can try the 7s. or a .30-06. .300 Win Mag can go quite a ways. Also, the more precise barrels can have a shorter life. So, if hunting, just be aware of that. The .308 might be short-ranged but it will go for 5k rounds fired before loosening up in accuracy.