I contend that the only choice would be a 30-06 bolt action with a 2-1/2--8 variable powered scope and backup iron sights.
Unless, of course, a lot of varmint hunting were contemplated. In that case, it would be a .270.
We don't hear much talk about the so-called "all-around rifle" any more because, as JB has pointed out, nowadays we have more money and can afford rifles for different purposes. While having one rifle might dictate a 30-06, many who have several don't need a 30-06 or a .270.
And if you could only use one bullet in your 30-06? I would pick the 180 grain Nosler Partition, again not considering varmints.
