In this article, we are going to cover how to zero a red dot optic. The first thing you’ll need to do is mount your optic. Check out our other article on Where to properly mount your Red Dot.
What Does MOA mean on a Red Dot Sight?
Before you start the zeroing process, it is important to understand Minute of Angle or MOA.
MOA is the unit of measure that is used to zero most optics. 1 Minute of Angle equals 1 inch of adjustment at 100 yards. Most red dot optics have 1 MOA adjustments which mean that each click will move the point of impact 1 inch at 100 yards. If you are shooting at 50 yards, each click will move the point of impact 1/2 inch.
If you are shooting at 25 yards, each click will move the point of impact 1/4 inch. Be sure to check your optic to confirm the click value of the MOA adjustment before you start this process. For a deeper look at MOA, check out the NSSF’s article on the topic here.
For the purposes of this article, we are zeroing an AT3 Tactical RD-50 Red Dot which has 1 MOA adjustment.
Zeroing a Red Dot at 25 yards
Start by firing a 3 shot group 25 yards to ensure you are “on paper” (If you aren’t on paper at 25 yards, you should use a laser bore sighter to get you on paper).
Examine where your shots hit. Assuming all of the shots are fairly close to each other, you can now use a small screwdriver or the back rim of a cartridge to start making adjustments.
First, begin adjusting the elevation. If your shots hit low, you need to raise the dot up. If they hit high, then you need to lower the dot. To zero the windage, it is the same process. Move the point of impact right or left as needed.
Now fire another 3 shot group to ensure you are zeroed at 25 yards. Keep firing 3-shot groups and make slight adjustments until you are sufficiently zeroed at 25 yards.
Zero a Red Dot at 100 yards
Now that you are zeroed at 25 yards, you can move out to 100 yards to set your zero. After sighting in at 25 yards, you should be on paper at 100 yards so just follow the same process as before but keep in mind that each click will move your red dot 1 inch at 100 yards.
The biggest thing to keep in mind is to work slowly and make small adjustments. Do not make adjustments after every shot and give yourself plenty of time to get the optic sighted in.
One Last Tip
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