Starvin Larry

“With DBC reticles, there’s usually no choice: 100 yards or meters main setting is required to make the other offsets correct. The way to pick the scope zero for the slower but more flexible reticles using MRAD or MOA subtensions is to figure out the point range first.

Point blank just means that a center hold would produce a hit on a target of a given size. Point blank on a torso of an enemy soldier maybe 275 yards, while on a prairie dog only 60 yards.

So the same rifle may be zeroed at 175 yards for a fight, but at 40 yards for a hunt. At the same time, this isn’t the only consideration for picking the zero distance.

If you have no expectation of encountering vary varmints up close, the zeroing distance should reflect the more realistic shooting environment.

So a 200-yard zero for the rodents just means your point-blank is 170 to 220, while shorter shots require holding under rather than over.

Similarly, if serious sniping is expected at 600 yards, it would make sense to zero that far and use a chart or a ballistic calculator to extrapolate shorter ranges. The error would be much smaller than with zeroing at a hundred and extrapolating to six.

The practical problem for most of us is the absence of ranges long enough to do that, and also the relative scarcity of actual long shots in either defense or hunting.”

https://blog.cheaperthandirt.com/zero-rifle-long-distances/