How To Sight In A Rifle Scope And Adjust As Needed

When shooting your rifle or carbine, you want to be as accurate as possible and that often means installing a sight or scope instead of irons. But for new gun owners or first-time sight users, you might not know how to sight in your optics. Today we are going to help you to sight in your scope and adjust it. In addition to that, we are going to answer some common questions.

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A scope or sight is a device used to aim your rifle. A red dot, cross hair, or similar reticule is used to line up your rifle with what you want to hit. But everyone has a different line of site, even when looking down the same sight. So when one person looks down a site, the reticle might be slightly off from where another person sees it.

Sighting in your scope is practice of adjusting a reticle to match where you want to hit. The process is relatively simple but there are some important points to take into mind.

What you are looking to do when sighting in your scope is to change the reticule to hit a zero point, the point at which a bullet will hit at a certain distance. The zero point is set to a specific distance such as 100 yards. Typically, the shortest you can sight in to is 15 yards. A good shooter will be able to use their zero point to shoot at different distances but will know to adjust where they aim, in order to hit the mark.

Different Types Of Optics

There are two main types of optics. A sight and a scope. A sight is a optic such as a red dot. You look down the sight and it has no magnification, it simply displays a red dot over your target. These are not perfect optics and are designed to be used for closer distances or when you don’t need to have a perfect view of the target.

A scope is designed to hit targets at range such as game or enemies. Scopes have magnification on them such as a 4x or 6x. Some scopes also have a variable magnification so that you can have it zeroed for different distances without needing to make adjustments in the field.

What Is Needed

Need to know what you will need to sight in your optic? Let’s take a look at what we think is necessary.

Optic
Optic Adjustment Tools (optic dependent but could be screwdriver, Allen wrench, proprietary tool, etc)
Ammunition (50+ rounds)
Target
Ruler in Inches (to measure distance from bullseye)
Monocular/Binocular (to see target at distance)

There are optional items that can make the process easier. One of those is a laser boresight to make boresighting and the whole process easier. Another optional item is a zeroing target. These targets have measurements printed on them so that a ruler is not needed.

A Note About Ammunition

Ammunition can make a difference when sighting in any optic. Most rifles have a number of different ammunition types and these can have different amounts of drop and other issues. For example, a low powder bullet might travel differently than a high powder bullet. The various different types of ammo can hit different points when you shoot and thus will change your zero point.

Use the same ammunition when trying to zero your sight as what you plan to shoot when you are done.

How To Sight In Your Scope

The first step to sighting in your optic is to mount it to your weapon. Attach the scope loosely onto the rail or attachment points and make sure it is straight before tightening it down. You will want to make sure that the sight is attached tightly so that recoil does not loosen the mounts. There should be no wiggle.

If you are using a scope that has ring mounts, make sure that the rings are tightened too.

Adjust The Reticle

Next, you want to make sure that the reticle is in focus when you look down the optic. Point your rifle at a solid color, such as the sky or wall. Look away from the optic and focus on something far away. Then look back down the optic quickly. Look away before you have time to focus on the reticle and what lays beyond.

If the reticle was focused, good. You can move on. If not, adjust the diopeter which is located close to the shooter’s end of the optic. Adjust the diopeter and repeat each step until your reticles are focused.

Boresighting Your Rifle

Before shooting any rounds, you can sight your scope (or sight) in with a method known as boresighting. It helps to get the process closer so that you have less work once you start slinging lead. Start by removing your bolt and point the rifle down range.

Look down the bore to point your rifle at a target. Then, being careful not to move the rifle, look down the scope. Adjust the elevation (up/down) dial until the reticle is on the same plane as the target. Then adjust the windage (right/left) dial so that the reticle is on target.

The idea behind boresighting is that you are aligning the optic so that your shots in the next step will be on the paper. You are not going to be able to get it spot on this way, but you will get it close. That is what matters.

Instead of taking out your bolt out, or on a rifle that does not make it easy to boresight in this style, you can get a laser boresight. A laser boresight drops into the bore and points a laser down range. It is both easier and more precise than taking the bolt out to sight in your optic.

Zeroing In

Now that you have your optic boresighted, it is time for the more entertaining part of the process. Before shooting, make sure that you have a stable shooting position set up and that you have a way to measure how far off your shots are on the target.

This can be done with a ruler, a zeroing target, or estimation. Note that estimation will take longer and be less accurate.

Start by taking three shots at the target. Make sure that you hold your rifle stable and that all three shots are aimed at the bullseye. Unless you are incredibly good at boresighting or incredibly lucky, these shots will not hit exactly where you want them to be.

Measure how far off the bullseye these shots were and now we are going to adjust the scope. If sighting your rifle in at 100 yards, ¼ of an inch adjustment will be 1 click on your windage or elevation dial. For reference:

So if you are off the target by an inch to the right, you want to turn your windage dial 16 times (clicks) to the left. This is assuming that you are zeroing at 25 yards, a common distance for AR style rifles. Adjust the optic as needed.

Fire three more shots at the target. Hopefully you will now be closer to the bullseye. You will then readjust the sight. Continue repeating the process until you are hitting the bullseye consistently. Until you have done the process multiple times, you will probably need to repeat the steps several times in order to get zeroed perfectly.

Cowitness or No Cowitness

For tactical shooters there is something to consider when buying a scope or sight. Cowitnessing is the ability to raise your optic off the gun to allow for iron sights to still be visible when looking down the scope. This is helpful for those who want to have a versatile option between distance and close range.

The reason we are mentioning this, is that a cowitnessed sight or scope will need to be readjusted when moved off the gun. Typically, you are moving the sight about half an inch to an inch above where it would normally sit and thus the up/down will have to be adjusted. You might also have to adjust the left/right after moving it.

Sighting your scope (or other optic) in will become easier with time. It will also become more enjoyable as you learn to do it. One important thing to keep in mind is that dropping your rifle, hitting it against something, or otherwise causing jostling to the scope can cause it to lose its zero. This all depends on the quality of your optic, just make sure to take test shots before relying on your optic if you think it may have been knocked off kilter.

Sherman
Updated on July 20, 2020