When Is Parallax Adjustment Needed?

What you need is for both reticle and target to be on the same focal plane. For many hunters shooting at ranges of 250 yards or less, parallax isn't a concern. Most centerfire rifle scopes without parallax adjustment are set at 150 yards, which is fine for shots at distances under 250.

How much does parallax affect accuracy?

At short distances, the parallax effect does not affect accuracy. Using the same 4x scope at 100 yards, the maximum error is less than 2/10ths of an inch.

At what distance does parallax matter?

If shooting out to only 300 yards, you do not really need to be concerned about parallax. However, if you commonly shoot beyond 300 yards, then your scope should truly have parallax adjustment to clear up your target focus.