Red Dot Zero Distance Chart: 25m vs 36 vs 50/200 Yard Zeros

Zero your red dot at the wrong distance and you'll miss high at mid-range or low up close without knowing why. Here's how the common zero distances actually behave, and which to pick.

Why zero distance matters

A rifle red dot sits roughly 65mm above the bore on an AR-type rifle, so the bullet starts below your line of sight, climbs through it, and falls back through it further out. Your zero distance decides where those two crossings happen — and how far the bullet strays from point-of-aim in between.

Approximate trajectory chart

5.56 NATO, 16in barrel, 62gr, 66mm sight height. Values are approximate — your ammo and barrel will vary. Always confirm on paper.

Zero 25m 50m 100m 200m 300m
25m zero 0 +3cm +7cm +9cm 0
36yd (33m) -1cm +2cm +5cm +5cm -5cm
50/200yd (46m) -2cm 0 +4cm 0 -18cm
100yd (91m) -4cm -2cm 0 -6cm -25cm

Which zero should you choose?

  • 50/200 yard — the default answer. The bullet never strays more than about 4–5cm from point-of-aim out to 200m. Point at the middle, hit the middle. If in doubt, zero here.
  • 36 yard. Similar mid-range behaviour with a second crossing near 300 — popular as a battle zero where you want usable hits further out.
  • 25m. Convenient on short UK ranges, but you're 7–9cm high through the middle distances — you must remember to hold low at 100–200m.
  • 100 yard. Never shoots high — good for precision at a known distance — but drops fast past 150m and you must hold high up close.

Three practical notes

  • Short range? Use an offset target. If you only have 25m available but want a 50/200 zero, zero about 2cm low at 25m (see the chart row) and confirm at distance when you can.
  • Hold-under up close. Whatever your zero, at 5–10m the bullet strikes roughly a sight-height (5–6cm) below the dot — it hasn't climbed yet. That matters on small close targets.
  • Mount height changes everything. Taller mounts exaggerate the close-range offset — check the mount height chart and co-witness guide.

Step-by-step zeroing process: how to mount and zero a red dot. Understand your click values with what is MOA? and the MOA at distance chart. Browse rifle dot sights and AR-15 optics — UK-stocked, fast tracked dispatch.