6mm arc maybe not that versatile.

[Fess]

Feel free to correct me, but my understanding is that a major reason for the traditional preference of a "slow-as-possible twist" barrel was the inconsistent quality of bullets. IMO, that is less of an issue now. Years ago, Lijla barrels had an article (which I see has been updated) on this. When a bullet is slightly unbalanced, whether due to uneven thickness of the jacket or defects in the lead core, its actual center of rotation and center of mass will be slightly off. Other things, like the bullet being slightly misaligned or not obturating uniformly can also throw balance off. Since the bullet leaving the muzzle is spinning at high speed, it will literally jump to the side slightly as soon as it escapes the confines of the barrel. This, of course affects accuracy.

I found the updated article at Lilja : https://riflebarrels.com/a-look-at-bulle...and-twist/