To zero a red dot, you fire a small group at a close target, see where it lands, and turn the windage and elevation screws until the group sits under the dot.
Most people start at 25 yards (Aimpoint recommends 25 meters, which is close to the same thing).
If the sight is mounted right, only small adjustments should be needed, because red dots are built optically centered.
This guide shows how to count clicks, which way to turn the screws, and how to pick your zero distance.
Safety first. Follow the NSSF rules every time you handle the firearm: treat it as loaded, keep the muzzle pointed in a safe direction, keep your finger off the trigger until you’re ready to shoot, and know your target and what’s beyond it.
Zero only at a proper range, and follow the range’s rules.
The quick answer: 5 steps to zero a red dot
- Mount the sight tight, following the mount maker’s torque spec.
- Set a target at your starting distance (25 yards for most rifles and pistols).
- Rest the firearm on a solid support and fire a 3 to 5 shot group with the dot on the center.
- Measure how far the group’s center is from the aiming point, then turn the screws the right number of clicks.
- Fire another group to confirm, then check at your real zero distance.
That’s it.
The rest of this page fills in the details that trip people up.
How many clicks to move: the math in one table
Most red dots move about 1 MOA per click.
One MOA is about 1 inch at 100 yards, so the same click moves less the closer the target is.
Trijicon’s RMR manual puts it plainly: one click is about 1 inch at 100 yards or 1/4 inch at 25 yards.
| Target distance | One 1 MOA click moves | One 0.5 MOA click moves |
|---|---|---|
| 10 yards | about 0.1 inch | about 0.05 inch |
| 25 yards | about 0.25 inch | about 0.125 inch |
| 50 yards | about 0.5 inch | about 0.25 inch |
| 100 yards | about 1 inch | about 0.5 inch |
So at 25 yards with a 1 MOA sight, you need 4 clicks to move the group 1 inch.
Holosun’s manual gives a worked example: if your shots land 2 inches low and 1 inch right at 25 yards, you go 8 clicks up and 4 clicks left.
Not every dot is 1 MOA, though.
Some Holosun models (the HE509T, for one) move 0.5 MOA per click, so you’d need twice as many clicks.
Check your manual before you start counting.
(If MOA itself is fuzzy, our Mil vs MOA guide explains it in plain numbers.)
Which way to turn the screws
The arrow on each screw shows which way the bullet’s impact moves, not which way the dot moves.
The elevation screw sits on top and the windage screw on the side on the Aimpoint, Holosun and Trijicon sights covered here.
On a Trijicon RMR, turning toward the arrow (counterclockwise) moves impact up or right.
On the Holosun HS407C, counterclockwise moves impact up on the elevation screw, and clockwise moves it left on the windage screw.
Aimpoint marks its screws with “UP” and “R”, so you follow the arrow to move impact up or right.
The simple rule: move the impact toward the center of the target.
If you’re low, dial “up”.
If you’re right, dial “left”.
And if a screw starts to feel stiff, stop… you may be at the end of its travel, and Holosun warns that forcing it can damage the sight.
Which zero distance to choose
Pick your zero distance by the firearm and the distances you’ll really shoot at.
| Setup | Common zero | Why people pick it |
|---|---|---|
| Pistol red dot | 25 yards (Trijicon’s RMR procedure) | Matches typical pistol distances |
| AR-style rifle, general use | 50 yards (often called 50/200) | Impact stays within a couple of inches of the dot out to about 200 yards with common loads |
| Rifle, mostly longer shots | 100 yards | Simple to remember; dead on at 100 with holds above and below |
A note on the 50/200 zero: it only lines up at exactly 200 yards with certain barrel, ammo and sight-height combinations.
For most shooters it doesn’t matter much, because the bullet stays close to the dot across that whole range.
Still, confirm at the real distances once you can.
Only have a 25-yard range? Here’s the trick
You can get close to a 50-yard zero at 25 yards by setting impact a little below the dot.
With a typical AR, a 50-yard zero hits roughly 1.5 to 2 inches low at 25 yards, depending on barrel length, ammo and how high the sight sits over the bore.
Printed “25-yard adjusted” targets mark that offset for you, so you aim at one spot and dial the group onto another.
Treat this as a starting point.
Confirm at 50 yards when you get the chance, because your exact rifle may differ.
What to do when it won’t zero
If the group won’t settle, check the mount and your setup before blaming the sight.
- Shots wander between groups: check the mount screws, then re-torque to spec.
- Groups are large: use a better rest and shoot slower; red dots aren’t magnified, so small aiming errors show up.
- The dot is hard to see against the target: adjust the brightness until it contrasts clearly (Aimpoint’s manual says to set it to a comfortable level first).
- Zero changed after a move: a red dot moved to a different firearm needs a new zero (Trijicon says this in its manual).
Also keep your head in the same spot for every shot.
At 25 yards a red dot isn’t entirely parallax-free, so a little head movement can shift the impact (our parallax guide explains why).
Zeroing a magnified scope instead? Use our step-by-step scope guide with its click table.
FAQ
Should I zero a red dot at 25 or 50 yards?
For most rifles, 50 yards is the more useful zero, and 25 yards is a good place to start.
For pistols, Trijicon’s procedure uses 25 yards.
Can I zero a red dot at home?
You can rough it in with a bore-sight laser at home, as long as the firearm is unloaded and you follow every safety rule.
A true zero still needs live fire at a range.
How many shots per group?
Trijicon asks for at least three rounds per group, and Aimpoint confirms the zero with at least three shots.
Three to five is a sensible range.
Sources
- Aimpoint, “Zeroing your red dot sight: step-by-step guide”: https://www.aimpoint.com/support/zeroing-your-red-dot-sight/step-by-step-guide/ (25 m start, optically centered, screw directions)
- Aimpoint Micro T-2 manual (via Optics Trade): https://www.optics-trade.eu/blog/aimpoint-micro-t-2-red-dot-sight-instruction-manual/ (brightness, confirm with at least three shots)
- Trijicon RMR manual (PML1016-1 Rev 4): https://www.trijicon.com/uploads/page_content/PML1016-1_Rev%284%29_RMR_Manual_web.pdf (1 MOA per click, 1/4 inch at 25 yards, 25-yard zero, three-round groups, re-zero after changing platforms)
- Holosun HS407C instructions: https://www.optics-trade.eu/download/Holosun/Instructions_Holosun_Mini_HS407C_Optics_Trade.pdf (worked 25-yard click example, screw directions, adjustment limit)
- Holosun HE509T-RD manual: https://www.holosun.eu/media/26/77/1e/1693399221/HE_509T-RD_manual.pdf (0.5 MOA click value)
- NSSF, “4 Primary Rules of Firearm Safety”: https://www.nssf.org/articles/4-primary-rules-of-firearm-safety/
- Refactor Tactical, “50/200 Yard Zero”: https://blog.refactortactical.com/blog/50-200-yard-zero (about 1.5 inches low at 25 yards)
- ARFCOM, adjusted 25-yard zero targets: http://ar15.com/forums/t_3_18/529846_Sight_in_targets_for_25_50_yards_designed_for_Aimpoint_sights.html (25-yard offset targets, not fully parallax-free at 25 yards)
- M4Carbine.net, “36 yard zero – Red dot”: https://m4carbine.net/t/36-yard-zero-red-dot/259873 (50/200 only matches with certain load and barrel combinations)
- Checked 2026-11-04.