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

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.

How to Zero a Rifle Scope at 100 Yards

Step 1: Get to Know Your Equipment

Step 1

First, take stock of what equipment you have for the scope.

This step actually helped me familiarize myself with the different parts when I was first starting out.

There are many various rifles and rifle scopes, so having a better idea of which kinds you have can help you apply my tips more effectively.

Scope

Get familiar with your rifle 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.

I needed to adjust my shot by one inch at 100 yards to the right of my last, so I had to adjust four clicks to the right.

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.

The best thing to do is to constantly sight in your scope and become familiar with it.

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. I remember my shots weren’t lining up because I was using the wrong rounds!

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 bullet type 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 greatly helped me zero my 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 rifle rest to minimize any human error that may interfere with your test.

You might also want to level your riflescope to ensure that there aren’t any scope errors that can affect your shot.

Notepad and Pen

I learned that a handy notepad to write on with a pen is enough to help record the 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.

I also recommend having your local gun shop do this because it sets the stage for successful shooting if you are a beginner.

Plus, it’s never wrong to invest in quality mounting. If you have the cash, go for it!

Then, secure and keep your rifle steady on a solid 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, indicating that the magnification is set correctly.

If not, fine-tune the scope and point the crosshairs or reticle toward the dead center of the target.

Additionally, double check your windage and elevation adjustments.

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.

The best part? You don’t have to fire a shot (at least for now.)

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 what I personally use since I find it the easiest 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 shots in at the shooting range and use it as a basis for your adjustments.

I advise you NOT to rely completely on the boresight as it does not guarantee a perfect zero right away.

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

If you choose to go with one shot, 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 at the shooting range, check on how close your firing got.

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

First, 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 and then refit it again.

Second, a 1-10 inch difference means you only need to adjust the scope. 

You can measure the adjustment per click after calculating how much windage and elevation adjustments are needed.

For example, hitting 3 inches high at 100 yards would need around 12 clicks to zero toward the dead 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 rifle’s 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 for long-range shooting.

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.

Frequently Asked Questions

1_Frequently Asked Questions (FAQs)

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, zeroing a rifle scope at 100 yards is necessary because this range is more achievable by BEGINNERS and is appropriate for a wider range of shooting activities.

In my experience, 100 yards is a good starting point to practice zeroing, as it prepared me for zeroing at farther distances too!

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 you use higher magnification.

That’s why you would often see additional parallax adjustment knobs for high magnification scopes.

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.

What Does Zeroing Actually Do?

To zero your rifle primarily helps you hit your target with greater accuracy. To understand the logic behind this, I’ll have 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. 

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 bullseye on your target.

When you look through the scope, you see WHERE the bullet hits.

The scope acts as more than just a visual display of where the barrel is pointing at.

Can You Zero a Scope Without Firing a Shot?

Yes, it is possible to zero a scope without firing a shot. However, you’ll never really know if your scope is zeroed if you don’t fire a shot!

Tools like boresighters or collimators are good for sighting in at short distances, but I would use these as a last resort.

Final Words

Final Words

Zeroing a hunting rifle at 100 yards is essentially adjust, shoot, check, repeat.

With a little practice, zeroing at 100 yards (and eventually any distance for that matter) will come like second nature!

You’re ready to hit any target at its given distance, provided you’ve made the right adjustments and done enough research on your equipment.

To help you get started, I put together a list of the best rifle scopes under $300!

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

FINAL TIP: If you’re a beginner who has just bought their first scope, check out our guide on how to properly use a rifle scope to get you ready for your first shooting session!

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