How to Zero a Scope for Shooting Long Range

Getting a new rifle and/or a new scope is always exciting. However, until you make sure that these tools are properly zeroed in and calibrated, they aren’t going to be doing you much good. Whether you are going to be hunting, or you are going to the range and shooting for accuracy over long distances, you need to learn how to zero a scope.

The zero needs to be perfect. Even though an error in zeroing might seem minuscule at 100 yards, what happens when you need to shoot at 500 yards or 1,000 yards or more? You will find that those “small” errors become huge. You simply won’t be able to hit your target properly. Therefore, you must make sure you know how to adjust the scope correctly.

Fortunately, you will find that the process is not overly difficult, as long as you follow some simple steps. Below, we will look at what you need to know to properly zero your rifle.

Make Sure the Scope is Properly Mounted

Before you can even begin to zero the rifle properly, you must make sure that you have it mounted properly. Most of the time, shooters and hunters are going to be mounting their own scopes, so it pays to know how to do it the right way.

Most rifles today will be tapped or predrilled to add the scope base. They might have a groove or a rail system that you could use, as well. This makes it easier to add the scope. Always make sure that the mounting system and the scope that you have are compatible and that you have all of the pieces needed for mounting. For example, some scope rings might only fit onto certain scope bases.

Mount the base and add the scope according to the manufacturer’s instructions and be sure that you are aligning the reticle vertically and horizontally. Additionally, the reticle and the target should be clear at the same time. You can use the ocular focus ring to make adjustments until they are both clear.

You must make sure that the scope is level with the rifle when you mount it. Even small misalignments can cause you to miss and it will be impossible to zero the scope properly if there are mounting errors.

Keep in mind eye relief, as well. You need to make sure that the scope is far enough forward that the rifle’s recoil will not cause it to hit your eye when you are shooting. Typically, you will want to have three to four inches of eye relief. The last thing you need when you are out hunting or on the range is a fractured orbital socket.

If you aren’t sure you will be able to mount the scope correctly yourself, there is no shame in hiring a professional gunsmith to take care of it for you. This will ensure it is done correctly the first time, so you can then get on with the business of zeroing and sighting in the scope.

Rough Zeroing the Scope

Rough zeroing, which is also called bore sighting, is often used by those who need to quickly zero their scope. With this zeroing process, you are trying to get a bullet hole on paper, essentially. Keep in mind that this is just a rough alignment.

You will do this by removing the bolt on a bolt-action or by opening the action on a single-shot rifle. Then, you will place the rifle in a steady rest where it will be stable and won’t move. Put out a target 25 yards downrange and align the view through the barrel with the bullseye on the target. You will want to lock the rifle into position using sandbags at this point, so it won’t move.

Once you line up the barrel on the target, you will then look through the scope. Use the adjustments on the scope and move it until it is able to “see” the same image that you saw when you looked through the barrel.

After you have everything lined up, it is time to shoot and test. It can take a while to get good at bore sighting, but it is a skill worth developing. The goal is to get as close as possible to the bullseye when bore sighting. Once you see where the bullet holes are made in the target, you will then be able to know which direction you need to adjust your crosshair to fine-tune your zero.

When you try to bore sight a rifle, you must have a solid bench rest. Sandbags can help as well. If you prefer, or if you do not have a bench rest, you could always use a prone shooting position. The goal is to keep it as steady as possible. This helps to reduce the possibility of human error, and it will make adjustments easier.

Why Start at 25 Yards?

Since 25 yards is not truly long-range shooting, you might be wondering why you should start the zeroing process using the bore sight technique at this range. It’s because you want to keep the target close at first, so you can see where the bullet hits. This will make it easier to zero the rifle scope, and it will make hitting at a longer range easier. If you are on paper at 25 yards, you can then begin the true zeroing process.

What Should Your Zero Range Be?

One of the other questions that many will want to know is what the “perfect” zero range will be. Unfortunately, there is not an answer to this, as your needs might differ from another shooter. Someone who is shooting in competitions and who needs to hit targets at 1,000 yards will have a very different zeroing range than someone who is hunting from a stand and who might only need to hit targets at 50 yards.

The most common zero range is 100 yards, though, and that is what we will be discussing for the purpose of this exercise. Once you understand how to properly zero the rifle scope at 100 yards, you should not have any problem zeroing at other distances.

Zeroing at 100 Yards

It’s now time to properly zero the scope.

  1. After you are happy with the results from bore sighting, it is time to move out a target to 100 yards and take a shot. If you can hit the paper with your bore-sighted rifle with one shot, you will then take two more shots, for a total of three shots.
  2. If you can hit with all three shots, you will have what’s called a three-shot group. With those shots on the target, you will then estimate where the center of that triangle is located.
  3. Measure the distance from the bullseye and take note of the direction. Were the shots high, low, to the left, or right?

For this example, let’s say that you are two inches too high and three inches to the right of the bullseye at 100 yards. This means that you need to lower the shot by two inches and bring it three inches to the left to hit the bullseye.

Rifle scopes today have easy-to-use adjustments that will allow you to move the reticle or crosshair. Typically, a single click will move the crosshair 1/4” at 100 yards. This lets you know that it would take four clicks to move one inch at 100 yards. You can then do the math and easily calculate the adjustments you need to make to the scope’s elevation and windage dials.

For the two inches, you would rotate the elevation turret eight clicks down. With the windage dial, you would rotate 12 clicks to the left. These adjustments should help to zero the rifle and bring it onto the target.

You Have to Verify

Even though you have made the adjustments, it doesn’t mean that you are done zeroing your rifle. You still have to verify that the changes you made were correct and that you have done everything correctly. This means that you need to shoot another three-shot group. If you have done it right, you should find that the center of your group is close to the bullseye.

In some cases, you might have had one or more bullets hit the bullseye perfectly. However, there is always the possibility that you made an error, which will mean that you need to go through the process of measurement again.

This time, you should be closer to the target, so the adjustments that you make will be smaller. If the center of the group is still an inch to the right, you will need to adjust the windage dial. In this case, you would turn it another four clicks to the left.

Once you have made those extra adjustments, you will once again want to verify it. Take another three shots. This time, you should be even closer to the bullseye with all three of those shots. If there are still adjustments to be made, make them now.

Test it again with three shots. You should start to see that these groups of three shots are hitting close to the center of the target each time. Once you are able to ensure that you are getting the shots on target, you will have peace of mind regarding the accuracy of your rifle.

What About Ammo?

Because of the velocity and the design of bullets, you will find that the ammunition you are using can affect your zeroing. This means that when you zero your rifle, you should be using the same ammunition that you will typically be using when you are hunting or shooting. This ensures that the zero is true with the ammo.

What if You Have Trouble Zeroing?

In some rare cases, you might find that you are not able to properly zero your scope. This could be due to an issue with the way the scope is mounted. If the mounting was not done correctly, you will have trouble zeroing the scope. Check the mount, make sure it has been added properly, make sure the screws are tight, and then try zeroing again.

If you find that you are still having issues zeroing the scope, many times it is simply a matter of confidence. You might want to take it to a professional, who will be able to take care of it for you. Ask to watch while they zero the scope, so you will be able to do it in the future. It’s always better to be able to rely on yourself when it comes to these types of procedures with your firearms.

Zeroing Gets Easier the More You Do It

When you are first starting out with a new rifle and scope, the thought of trying to zero it at the 100-yard range on your own can be intimidating. The first time that you zero a rifle, it might take you quite a while to dial it in to where you need it. You might find that you are taking a large number of shots over the course of hours to get it right.

Don’t worry. Once you have done it a few times, you will find that it becomes easier over time. The next time you need to zero your scope, you will have more confidence, you will know how to make the adjustments to the scope, and you will be able to zero the scope in far less time.

Once you have a scope that is properly zeroed, shooting will be a pleasure. You can rest easy knowing that you are going to hit your target just where your crosshairs are pointing. This will give you confidence on the range and on the hunt.

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