Inherent accuracy is a myth. In fact, most of us seek precision as a means to evaluate a rifle. But here are some cold hard facts:
The cartridge chambering itself doesn't determine the precision of a rifle. The quality of the barrel has a huge influence over the precision of a rifle. Chamber dimensions vary depending on reamer design and desired bullet. Matching them correctly will result in optimal results, but that isn't done in most commercial markets. Factory rifles tend to be designed such that they are first safe, but then tolerant to a wide variety of cartridges. Some rounds get a reputation for being "inherently accurate" because the maker has done a good job of matching the reamer design to the bullets and cartridges the end-user will be using. Some cartridges are easier to "tune" because the capacity results in putting a bullet in the node which the bullet the user has chosen is optimized.
