Over the years I have heard of certain cartridges that were considered very accurate and others that were not considered to be a very accurate round.
The .308 and the .222 were considered accurate cartridges, while I have heard many times that the .3030 , .22 hornet and .22 mag were not very accurate.
From what I have learned over the years is that there are very few rounds of any type that cannot shoot very well if they are used in a rifle that is designed for accuracy. The .3030, .22 Mag and .22 Hornet have proven many times that if fired in a bolt or single shot rifle they can be just as accurate as any other cartridge. It appears that the accuracy of a particular cartridge was determined more by the fire arms that were produced for it than by the cartridge itself.

It's true that the 308 and 222 seem to intrinsically accurate cartridges, but your absolutely right in the fact that it's the platform that often makes those cartridges shine.

I spent quite a few years doing the bench rest thing. I had a solid bottom Heart barreled bench gun in 222. When the then new sleeved action bench guns came along I had to retire my 222 in favor of a new gun that I simply didn't want to put more money in. It wasn't that my 222 wasn't very accurate, but that the accuracy platform had moved on another step.

I don't have anything to add, I just want to follow the banter.