What scope features matter for airguns?

Look for adjustable parallax (AO or side focus) that goes down to 10 yards; airguns are often shot inside the standard 100-yard parallax setting on firearm scopes.

Look for an airgun rating, second focal plane reticles for ease of use at typical airgun ranges, and a magnification range from about 3x to 12x for hunting or 4x to 16x for longer range. Mil-dot or BDC reticles help with the loopy airgun trajectory. Avoid bargain-basement no-name scopes; they fail under spring piston recoil.