How to Sight in a Red Dot – The Basics

When you mount a red dot on your rifle, shotgun, or pistol, you’ll need to line it up correctly to ensure your shots are accurate. Here are the basics of zeroing in and few different techniques on how to sight in your new red dot. 

The Basics of How to Sight in a Red Dot

Before you get started in zeroing your red dot, you’ll need to understand the importance of the MOA (minute of angle)

An MOA is 1/60th of a degree and spreads at approximately 1″ per 100 yards. So, imagine that you’re shooting at 100 yards. In this case, your MOA would be 1″. At 200 yards, it’s 2″, 300 yards, the MOA is 3″, and so on. 

Based on this measurement, you’ll need to calculate your shots in 1″, 2″, 3″, or higher increments, depending on the distance. 

Now that you have this down, it’s time to work with the red dot. 

When you open up your sight, you’ll see a symbol, letter, or word that indicates the adjustments you can make. 

The elevation control would most likely be represented by the word “up,” with an arrow illustrating the direction to turn the dial. The windage control should have an “R” and feature an arrow for the same purpose. 

The number of MOAs per click depends on the type of red dot you have, but most will adjust to only one per click. (Those with finer alignment increments are typically more expensive.)

Now, imagine that you’ve just taken your first shot at 100 yards. Your shot was off to the left, and a little low. Here’s how to sight in a red dot based on an example using a grid:

  1. On the grid, you observe that your shot was about six MOA too low. So, you’ll need to turn the elevation up by six clicks. 
    1. Note: Keep in mind that the arrow indicator can be backward. Verify if the indicated direction is correct, so your zeroing process is accurate. 
  2. Now, even though you’re level with your target, you’re still off by another five MOA to the left. Turn your windage five clicks. 

*Note that if you need to go down or to the left, you’ll need to turn the adjustments opposite of the indicated direction. 

You might not have the luxury of using a grid or otherwise knowing the precise number of MOAs your shots were off by. 

If this is the case, remember that you need to make corrections based on the increments that correlate to your shooting distance. This will take trial and error, but you’ll still be able to zero. 

How to Sight in a Red Dot Scope Without Shooting

You won’t always be able to do trial and error firing when sighting in a red dot. In these cases, you’ll need to adjust your technique to attaining high-level accuracy when it is finally time to shoot. Here are some easy visual zeroing methods you can use without firing a single shot:

  • Rest your firearm on a stable platform and line the barrel’s center up with the sights on your target. Zero the red dot with the target point by adjusting the windage and elevation, and there you have it!
  • Stand in front of a mirror at a suitable distance and align the red dot with the firearm’s barrel. (Of course, you need to verify that your gun is not loaded at this time.)
  • Using a laser boresighter, look into the scope to see the laser point. Center the crosshairs, and your weapon will be sighted in correctly.
    • You’ll use a similar technique when zeroing with an optical boresighter. Instead, you’ll just need to center the crosshairs on the lens’s grid.

Best Distance to Sight in a Red Dot

The ideal distance for sighting in a red dot may change based on the firearm you’re using it with. With any weapon, though, you won’t be able to get your sights 100% precise. 

Still, your sight-in distance can reduce the likelihood of missing your point of impact (POI). With this in mind, the best distances for sighting in a red dot for pistols and ARs are:

  • Pistol: Based on a few tests, the best possible range to zero in your red dot is 25 yards. Comparisons between 25, 12, and 5 yards demonstrated that sighting in at 25 yards gave the least dispersion of all and resulted in the most consistent accuracy in groups at all three distances. 
  • AR: It’s best to zero at 50 yards for an AR-15. This is much easier than trying to sight in at 200 yards (even for beginners) and it’ll help you maintain accuracy when shooting at 25, 50, and 200 yards. (You will be a few inches off, but not too much.) Plus, this is the most practical distance for self-defense.

How to Sight in a Red Dot on Your AR

The process of how to sight in a red dot on an AR-15 slightly differs from what you’ll need to do with other firearms. Here’s a quick look at what it takes to zero in for this gun:

  1. Set your target at 50 yards. 
  2. Separate the upper and lower receiver, remove the charging handle, and bolt carrier group. This way, you can clearly see through the barrel at your target. 
  3. Align the dot so that it is on your target. 
    1. Lining up the red dot with the iron sights is not how you should get on target, as they are separate aiming systems. 
  4. Reassemble the gun. 
  5. Turn the red dot’s brightness level down to its lowest setting to create a fine aiming point. 
  6. Fire a group and determine what adjustments you need to make to elevation and windage for accurate firing. 
  7. Repeat Step 6 until you’re sighted in perfectly.

How to Sight in a Red Dot on Your Pistol

As you’ve learned, different firearm types require small technique changes to ensure you get your red dot sighted correctly. Follow these steps below to zero a pistol-mounted red dot:

  1. Distance the target at 25 yards (or 10, as some experts recommend). 
  2. Turn down the red dot’s brightness for a finer aiming point. 
  3. Shoot a group to get a feel of how far off you might be. 
  4. Adjust your windage and elevation as needed. 
  5. Repeat Step 3 and continue doing so until you’re zeroed perfectly.


To sight in a red dot, you’ll need to be mindful of the target’s distance and MOA per click to ensure you’re making the appropriate corrections to the windage and elevation. 

There are ways to zero without ever firing the weapon at all, but this is easier to do with a rifle since you can disassemble it and look down the barrel to verify your red dot is on sight. On the other hand, it’s best to fire a group with a pistol and use a trial and error method to sight in. 

Joseph Fox

Joseph Fox

Joseph Fox writes on a variety of topics ranging from reloading ammunition to gun cleaning. He has been featured on various publications like thetruthaboutguns, Sofrep & many more. Joseph is also the founder of Gunloading, where he reviews different types of reloading & firearm products available on the market.