How to Zero a Rifle Scope?

A quality scope is an excellent addition to your favorite rifle. It will add clarity to target images and help to extend the distances you shoot over. From there, and with regular practice, your shot accuracy should come on in leaps and bounds. However, to achieve consistent accuracy, your scope needs to be correctly zeroed.

Learning how to zero a rifle scope should be part of every shooter’s learning curve. This is the case, even if you are new to the world of rifle shooting. Zeroing-in is not an overly difficult task, but preparation, patience, and having no time pressure will certainly help get the job done successfully.

Once completed, you will be ready to hit the hunting trail or range with a spring in your step!

how to zero a rifle scope

How To Zero a Rifle Scope in Seven Straightforward Steps?

Ask a bunch of seasoned rifle owners how to zero-in a scope, and one thing is for sure, a variety of methods will come your way. This is because there are lots of different ways to get the same result.

Zeroing-in is often called sighting-in. They mean the same thing, and both terms will be used as the process is explained.

The purpose of zeroing a scope is to ensure that the bullet will follow the expected LOS (Line Of Sight). The goal is to adjust your rifle scope, so that fired rounds accurately hit the target at a specific distance. When zeroing-in, you are taking into account the actual scope being used and the ballistics of the ammunition you will be using.

Sighting-in distances and the load you use will be explained shortly, but let’s keep these steps in order!

1 Preparation…

Before even thinking about sighting-in you need to be sure your scope is correctly installed. Whether you are using a scope ring and base setup, a rail and scope ring set up, or any other type of mounting, one thing is for sure: your scope must be fitted in the correct manner.

Any scope that is loose or incorrectly mounted means you will be wasting your time trying to zero it in.

Make sure that all screws are torqued to the manufacturer’s recommended specs. Also, double-check that the mounting setup you are using really is compatible with the scope you have.

how to zero rifle scope

Check eye relief…

Once satisfied that the scope is mounted correctly, you then need to check eye relief. This is the distance between the eyepiece (the rear scope lens) and your eye. While experienced shooters may be happy with 3-inches, most shooters should look at a minimum of 3.5 to 4-inches of eye relief.

Getting your focus lined up is the next step to check. To do this, the ocular focus ring should be adjusted to your eye. This means that when looking at a target, you should clearly see both reticle and target at the same time.

Scope 101…

Once that is done, have another check of the scope’s features and functionality. These are presented as knobs, buttons, and wheels! Familiarity with exactly how your scope works will make effective use much faster. In this respect, here are two particularly important features:

Windage and Elevation turrets

Understand where each is positioned, what the MOA (Minute of Angle) measurement is, and how incremental adjustments are made on each.

The Crosshair (Reticle)

Make sure it is perpendicular (90 degree axis) to your gun’s bore.

2 Gun Stability and Leveling

A gun rest or gun vise is a really useful piece of kit and effective for a variety of uses. Three that immediately spring to mind are:

Weapon cleaning and maintenance

This is because they will hold your gun firmly in place and allow you to work with both hands.

Scope mounting

When mounting a scope to your rifle, it is important to have your weapon secured and level throughout. A quality gun vise such as the Tipton Best Gun Vise for Cleaning, Gunsmithing and Gun Maintenance or the very affordable HOPPE’S Gun Vise are particularly useful for this type of work.


During the actual firing of your rifle, weapon stability is an absolute must. There are a variety of ways to achieve this. Some shooters will use sandbags; others may have a tripod. However, the use of a gun rest such as the TWOD Outdoor Shooting Rest Bags or the Caldwell Steady Rest NXT Adjustable Ambidextrous Shooting Rest, which has also been designed to assist with sighting-in, is a very solid option.

how to zero the rifle scope

Using such a quality gun rest will ensure your rifle is kept rock steady throughout the process. Not only that, it can reduce recoil by up to 95%.

I am not suggesting that you should purchase either a gun rest or gun vise purely for sighting in. But, the value in terms of flexible use for a variety of applications cannot be underestimated. A wide choice of both at varying prices are readily available. While this is an investment, it should be seen as a worthwhile one due to the regular use you will put it through.

3 Bore Sighting Will Save You Time

Bore sighting is a relatively quick procedure that will save you time during the sighting-in process. The purpose of bore sighting is to make sure that the center of your rifle bore (barrel) aligns with the scope sight. This can be carried out manually or by using a bore sight tool.

Two superb options are the MidTen Bore Sight Cal Red Dot Boresighter 223 5.56mm Rem Gauge (options available for different calibers) and the Pinty Red Laser Bore Sight Kit for .22 to .50 Caliber.

The manual bore sighting process is seen as sufficient for many shooters, and that bore sighting tools are certainly not a “must have.” However, these tools do offer benefits in terms of speed, efficiency, and accuracy. Those looking at bore sighting devices will find that laser models are the most popular, but magnetic versions are also available.

4 Load and Target Distance

You should then decide on the type of load (ammunition) you will be using on a regular basis. The choice of load used should be one that suits your shooting applications and style. However, once you have sighted-in with a particular load, this is what you should stick with when out shooting.

This is because of the wide choice of cartridges available from different manufacturers. While they may be similar, they are not the same! Depending upon the brand, they will differ in shape, weight, and load. Staying with the cartridge type and brand you use for sighting-in when out shooting will give you load consistency.

What if you want to change your load?

That is not a problem at all. Each time you change load, just go through the remainder of the sighting-in process explained below.

how to zero rifle scope guide

Your target then needs to be set up. This can be done out in the open as long as you have a safe place to shoot, a solid backstop, and the ability to accurately measure distances for target placement. Perhaps an easier option is to use your local shooting range. This is because all safety aspects are in place, and targets are accurately set at different distances.

In terms of target distance for sighting-in, there is no predefined distance you must use. To give examples of sighting-in distances, some keen hunters will do this at 200 yards, while novices may want to start at 25 yards. But, the most common distance is 100 yards, and that is the one used in this explanation.

5 Sighting-in Shots

Some shooters go with only one sighting-in shot. However, I would recommend taking a group of three shots. This is because it will help you clearly define the impact and distance between each shot in the group. It will also identify any obvious (unintentional) rifle movement between these shots.

Before taking your first shot, check your scope is properly focused and parallax is correctly adjusted. Line up the crosshairs with the bullseye on your target, and then take three slow, careful shots. You should pause between each trigger pull as the intention is to get off the cleanest shots possible.

Once you have fired these three shots, check the target to see how well grouped they are. The aim is to group the three shots as close to the bullseye as possible, but do not worry if these shots do not land there. It is more important they hit the target and are closely grouped.

6 Adjustments

If you find that all three shots have completely missed the target, it is very clear something is wrong. Rather than trying to make large adjustments, you should check the fitting of your scope. The best way to do this is to unmount the scope, mount it again and repeat the shot process.

Time to make the adjustments…

If the group is on the target, but away from the bullseye, you will need to make adjustments. These adjustments are necessary in order to move your POI (Point Of Impact) closer to the bullseye. To do this, look at your scope’s turrets to establish how many clicks are needed to move the POI 1 inch at 100 yards.

It is usual for the turret on top of your scope to be for elevation. Through adjustment, it moves the bullet impact up or down. As for the side turret, this is for windage and is right or left adjustable.

how to zero your rifle scope

Minute of Angle…

The most common measurement on scopes is 1/4 MOA (Minute Of Angle). This means that four clicks are required to adjust 1 inch at 100 yards. Using this 1/4 MOA measurement, let’s give an example of what adjustments would need to be made if:

Your group is 1-inch above the bullseye and 2-inches to the right. This means you need to adjust your reticle four clicks down and eight clicks to the left to get bullseye accuracy.

Some scopes come with different measurements, such as 1/8 MOA and 1/2 MOA. If this is the case with your scope, just divide the fraction into 1-inch. That would mean eight clicks and two clicks per inch of movement for these MOAs.

Time to see the improvements…

Once you have dialed in these adjustments, it is time to fire another three shot group at the bullseye. If the adjustments made leave your group in the bullseye, that is your sighting-in completed. If you are still out, note the distance of this shot group to the bullseye and repeat the adjustments as above until you are hitting the bullseye.

7 A Word To The Wise!

During the sighting-in process, it will pay you to log all relevant details for future reference. Examples include the date, weather conditions, location, load used, and adjustments made. However, this should not be a one-off. Smart shooters keep an accurate and consistent record of all shooting sessions.

In shooting circles, this is known as DOPE which is an acronym that is quite the opposite of dopey! – Logging “Data On Previous Engagements” is something that all shooters should get into the habit of. It relates to information gathering on such things as previous range visits, any training completed, and individual shooting sessions.

The shooting session details you will log include the weapon load, scope settings, wind conditions, humidity, and the angle of shot above or below horizontal. Recording these details will increase your overall knowledge base of various shooting situations. It will also help give a better POI estimation of the round you are firing with the rifle you are using.

A crucial part of successful shooting is consistency. Using your gathered DOPE detail gives you that. This is seen through your ability to reapply that data on each new shooting session and to increase your chances of repeated target hits.

Need More Great Advice or a New High-Quality Scope?

Then take a look at our informative guides on What Do The Numbers Mean on a Rifle Scope?, How to Lap Scope Rings?, How to Mount a Scope?, What is MOA on a Scope?, How to Zero a Rifle Scope at 100 Yards?, as well as our in-depth comparison of Red Dot vs Reflex Sights.

And if you’re old scope is past its best, then it’s time to get a shiny new one. So, check out our reviews of the Best Air Rifle Scopes, the Best Low-Light Rifle Scope, the Best Scout Scopes, the Top 10 Best AR15 Carry Handle Scopes, or the Best Low Light Rifle Scope you can buy in 2023.

Final Thoughts

Knowing the best way to zero a rifle scope should be seen as part of your best firearms practice. The process is not difficult; it just requires a little time and patience.

Don’t hesitate to sight-in at the start of the hunting season, before any hunting session, or on a regular basis if competing. The other thing to remember is that if you change your load or brand of cartridge, then sight-in again. This will ensure you are getting expected accuracy.

Regular range practice and/or shooting sessions are necessary if you are to get the most out of your sighted-in scope. By doing so, the rewards will be seen through improved consistency and greater accuracy.

In turn, this will lead to increased shooting satisfaction, and that has surely got to be what all rifle owners are after!

Happy and safe shooting.

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About Gary McCloud

Gary is a U.S. ARMY OIF veteran who served in Iraq from 2007 to 2008. He followed in the honored family tradition with his father serving in the U.S. Navy during Vietnam, his brother serving in Afghanistan, and his Grandfather was in the U.S. Army during World War II.

Due to his service, Gary received a VA disability rating of 80%. But he still enjoys writing which allows him a creative outlet where he can express his passion for firearms.

He is currently single, but is "on the lookout!' So watch out all you eligible females; he may have his eye on you...

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