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.

Which zero should you choose?

• 50/200 yard (46/183 m) — 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 (33 m). Similar mid-range behaviour with a second crossing near 300 yd (274 m) — popular as a battle zero where you want usable hits further out.
• 25 m (27 yd). 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 (91 m). Never shoots high — good for precision at a known distance — but drops fast past 150m and you must hold high up close.

Metric equivalents used on British ranges

The zero names are American and the ranges are not. British ranges are laid out in metres, so a yard-named zero has to be converted before you can set it up at your club. The imperial names are kept throughout this page because they are what these zeroes are actually called, and what shooters search for — but here is what each one is in metres.

Do not treat 50m as 50 yd. The difference is 4.3m. Zeroing at a true 50m rather than 50 yd pushes the far crossing out from roughly 183m to roughly 200m, which gives you a 50/200 metre zero — the same idea, very slightly flatter, and arguably the more sensible one to shoot in Britain. Either is fine. What is not fine is thinking you have set one when you have set the other, so write down which you used and confirm it on paper.

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, with £5 tracked UK delivery.