How to Zero a Rifle Scope at 100 Yards: 5 Easy Steps

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How to Zero a Rifle Scope at 100 Yards

The accuracy of your shot is only as good as the quality of the rifle scope you have. With a high-quality rifle but mediocre scope, you won’t be able to hit the target as easily.

But that’s exactly why we’ve decided to write this scope article on how to zero your rifle scope at 100 yards for better shots.

It might take some time, but you’ll find out how to zero a rifle scope and improve your accuracy in just roughly under 10 minutes.

Step 1: Get to Know Your Equipment

Step 1

First, take stock of what equipment you have for the scope. There are many various rifles and rifle scopes, so having a better idea of which kinds you have can help you apply our tips more effectively.

Scope

Get familiar with your scope first. Find out whether it uses a minute of angle (MOA) or milliradian (MIL) system of measurement to help you calculate your adjustments.

For example, one-quarter-inch at 100 yards usually equals one-click for MOA rifle scopes.

So if you need to adjust your shot on the scope by one inch at 100 yards to the right of your last, you need to move four clicks to its right basing from your scope.

There’s heavy debate on which scope measuring system is better to use for a 100 yards distance. What matters is that you know how to use the one you have.

Bullets

Next, you also need to know the type of ammunition you’ll be using for a 100 yards distance. Things like the weight and size of the bullets can affect their trajectory.

Since the point of impact is determined by your aim and the effect gravity has on your bullets, make sure to take these two factors into account.

For our 100 yard zero, stick to just one type of bullet so that any differences among the scope settings can be fully attributed to the zero process.

Boresight

This part is optional, but a bore sight can be of great help as you zero your rifle scope. It can save you from using too much ammunition and shoulder wear and is usually the laser or magnetic kind.

Rifle Rest

To keep your shots steady, you can use a rest to minimize any human error that may interfere with your test.

Notepad and Pen

A handy notepad to write on with a pen is enough to help you record your adjustments on the scope.

Step 2: Set Up Your Rifle

Step 2

The next step is to set up your rifle scope, rifle, and target.

Make sure the scope is fitted level and torqued with the appropriate settings on the rifle.

You can also have your local gun shop do this instead because it sets the stage for successful shooting, and it’s never wrong to invest in quality mounting. If you have the cash, go for it.

Then, secure the rifle on its rest so that it’s stable and your shooting will be free of human error (for the most part, not 100% free).

Now, look through the scope and you should see a clear image. This indicates that the magnification is set correctly. If not, fine-tune the scope and point the crosshairs or reticle toward the center of the target.

Step 3: Fix The Boresight (Optional)

Step 3

If you’re using a boresight, you can start the bore sighting process at this point. If not, you can move on to the next step for your scope.

Basically, this means aligning the rifle bore with the scope and sights to control the trajectory of your projectiles.

If you had your scope mounted at the gun shop, they usually take care of the bore sighting as well.

There are a few differences depending on the type of boresighter you have:

Visual

With this kind, you position the middle of the rifle’s barrel with the sights by eye. Although, it can take you a while and is applicable only when you intend to shoot from a certain distance and no more.

Laser

A laser bore sight is popular and easy to use for a scope. The laser is found inside the muzzle where a beam of light will guide your aim for a 100 yard distance.

Magnetic

This type uses a magnetic strip to attach itself to the end of the barrel. You look through your scope then adjust the scope crosshairs to the grid.

Step 4: First Shot

Step 4

Once everything is aligned, you can get your first shot in and use it as a basis for your adjustments.

PRO TIP: Don’t solely rely on a boresight; it doesn’t guarantee a perfect zero right away.

Different guides recommend either one or three shots for your first assessment.

If you choose to go with one, examine the first point of impact and use it as your main starting position. Going with the three-shot; however, can let you better track if your rifle has moved.

Also – and this is important – start at a distance of 50 yards, not 100 yards.

The reason why: It’s easier to make adjustments with a closer range of 50 yards than at our goal of 100 yards right away. Some even use a 25-yard distance for this step.

Step 5: Make Adjustments

Step 5

After firing either a one- or three-shot test, check on how close your firing got.

There’s a lot of ways this can go, but let’s take a look at a few examples:

#1: A complete miss indicates a bigger adjustment is needed to zero. The problem could be in the fitting of your scope so try to unmount it then refit it again.

#2: A 1-10 inch difference means you only need to adjust the scope. You can measure the adjustment per clicks after calculating how much to adjust horizontally and vertically.

For example, hitting 3 inches high at 100 yards would need around 12 clicks to zero toward the center for most scopes.

After each adjustment, go for another test shot and see if there is any change.

If not, try again.

You know you’re on the right track if the shots get closer to the target. If not, keep making adjustments until the accuracy improves.

Don’t Give Up

You can now zero at a 50-yard distance. This means you can go further and zero at 100 yards. Simply repeat the steps and do another assessment. Then, make finer adjustments afterward.

Don’t forget to log all of your adjustments at each distance, at 50 yards and then at 100 yards, because any change in distance requires different adjustments.

FAQs

FAQs

#1 Why Should I Zero at 100 Yards?

A 100-yard zero is the set rule when it comes to zeroing your rifles. However, you can zero at a shorter distance like 25 yards as well.

Still, you should zero at 100 yards because this range is more achievable by beginners and is appropriate for a wider range of shooting activities.

It hits the sweet spot for short-range shooting at 25 yards as well as long-range ones that reach up to 300 yards.

Most scopes are already focused at 100 yards as the set distance to avoid parallax error.

Parallax error occurs whenever we use higher magnification.

Here’s a complete definition: When your eye shifts even just a bit to the left or right, the aim on your scope can look off-center even if it was already at zero.

#2 What Does Zeroing Actually Do?

To zero your rifle primarily helps you hit your target with greater accuracy. To understand the logic behind this, we’ll need to talk about physics.

When you fire your rifle, the bullet doesn’t travel in a straight line. As it travels along its trajectory, gravity is pulling it down until it reaches the target.

So instead of a straight shot, the bullet drop appears closer to a slight arc since the speed of the bullet somewhat minimizes the pull of gravity.

What’s more, the trajectory of the bullet drop curves downward the closer it gets to the target because the speed of the bullet gradually slows down due to air resistance.

And so, to zero the scope means making up for the bullet drop. It also helps you land a bulls eye on your target.

When you look through the scope, you see where the bullet will actually land; the scope acts as more than just a visual display of where the barrel is pointing at.

Final Words

Final Words

Now that you know how to zero your rifle, you’re ready to hit any target at its given distance, provided you’ve made the right adjustments and did enough research on your equipment.

You must understand the whys when you zero your rifle at 100 or 50 yards’ distance, so you can take the main principles & steps of our guide and apply them during whichever shooting activity you love to do.

For good rifle scope options, read through our article on the Best Rifle Scopes All Under $500.

About the author

Christopher Wade

Christopher Wade

Christopher Wade is a true outdoorsman. After spending most of his career as a firearms expert and instructor in Nebraska, he retreated to the great outdoors to enjoy retirement.

Christopher’s expertise in handling firearms and hunting gear are what propelled him to create the Shooting Mystery blog. He hopes for all readers to gain useful and practical knowledge for enjoying their time outdoors.