Our editors pick the products & services we write about. When you buy through our links, we may get a commission. Learn more.

How to Zero a Rifle Scope at 100 Yards for the Best Accuracy

If you like hunting or competitive shooting, you must definitely be familiar with zeroing in a rifle scope. Zeroing a rifle scope is very important for long range shooting because it improves your accuracy for long distance shots. Most shooters prefer to zero their rifle scope at a short distance like 25 yards, others zero their scope at 50 yards, but 100 yards zero is the optimum range. This is because it is usually within range for most shooters.

The steps to take when zeroing a rifle at any given range are simple and straightforward. In this article, we will learn how to zero a rifle scope at 100 yards.

Zero a Rifle Scope: Meaning

How to Zero a Rifle Scope at 100 Yards for the Best Accuracy

Before we begin, let’s define what it means to zero a rifle scope. When you zero a rifle scope, it means that you adjust the rifle scope in a way that it has the crosshair centered on the bullet hole, which is also known as ‘sight.’ This means that before you zero a rifle scope, you must first set up the target and take the first shot. After shooting, there should be a bullet hole (bullet impact) on your target paper. It is this bullet impact point that you would use to zero your rifle scope. Your rifle scope is zeroed when you hit the target dead center or in less than a 2-inch deviation.

What Is Required To Zero A Scope?

To accurately zero your rifle, you will need the following items.

Rifle scope: This is the major piece of equipment for zeroing your rifle. Check if the scope is properly mounted on the rifle. The bolts and rings must securely connect the scope mount to the scope base.

Ammo: When you zero for a given distance, the quality of your ammo would influence your aim. Bullets drop at different rates depending on their length, velocity, weight, and projectile type. Hunters should adhere to a single bullet type because changing your ammo will change your zero.

Bore sights are classified as either laser or magnetic. You’ll save a lot of ammo if you boresight.

A Gun vice keeps your gun entirely steady as you zero it. It reduces the possibility of human mistakes and should be used while setting up your zero.

Diary: Some shooters use a book and a pen to perform calculations while trying to set up the zero.

Why Zero Your Rifle Scope at 100 yards?

When it comes to zeroing a rifle scope, there are no rules that say you must zero a rifle at a particular distance. You can zero a rifle scope at a distance of 25 yards, 50 yards, or even 150 yards if you choose. However, for some reason,  most shooters have chosen a distance of 100 yards as their standard range for zeroing. This is because most hunters and shooters have their shooting activities within the 100 yards range.

Rifle scope makers usually set the parallax scope adjustment to 100 yards. If you shift your eye to the right or left as you look through the scope, you will notice a tiny movement on the scope. It shifts the target slightly to the right or left of the crosshair. Some scopes allow for varying ranges of parallax adjustment, although most of them come with parallax that is set at 100 yards, making it easy to zero your scope at that same distance.

Zeroing a scope at 100 yards is simple, and even amateurs can easily zero a scope at that distance without any challenge. Most shooters prefer the 100 yards zero because it is far enough away to see if the scoped rifle is aligned with the bore. When setting your zero at 100 yards, check to see if the scope and bore are aligned.  This does not mean that your scope should always be zeroed at 100 yards. You can also zero your scope for a longer range. 

If you want to go hunting, you will most likely have to do medium range or long range shooting and your targets would be between 200 yards to 300 yards. If you sight your scope at 200 yards, the bullet drop will only be a few inches compared to when you zero the scope at 100 yards.

Although it might not be easy to zero a scope at 200 yards. The goal here is to begin at 100 yards and progressively increase your zero as you improve your shooting skills.

If you are hunting in the woods your shooting range should not extend beyond 200 or 300 yards. This kind of medium range shooting should be easy if you zero at 100 yards and then adjust your elevation for a 200-yard shot. If your average range is 200 to 300 yards, start at 200 yards. That should cover most medium range shooting between 100 yards to 300 yards.

Record Your Shot Accuracy

It is important that you take note of your ammo, wind, range, and so on so that you can precisely replicate those shots when needed. If you zero for certain ammo and then swap to another ammo like Remington magnum cartridge, your entire setup would be thrown off. The velocity with which your bullet leaves the muzzle changes, the same thing happens to the trajectory.

If the parameters change, your previously aligned rifle and scope will go out of alignment. Bullet trajectory tables and charts, as well as ballistic calculators, can be used to compensate. 

Why Is Zeroing Necessary?

Generally, zeroing your rifle scope can make or break your hunting expedition. A scoped rifle will improve your long range shooting accuracy and allow you to shoot a dead center shot.

You must remember that a bullet does not move in a straight path when fired from a rifle (bullet drop). Gravity begins to drag it down immediately after it exits the barrel of your rifle. Note that gravity has a low effect on the bullet because it is moving so quickly. However, when the bullet slows owing to air resistance, the drop increases. 

To compensate for bullet drop, you must zero the rifle scope such that it shows the impact point (where the bullet will hit) at a given distance rather than the direction of the barrel. The direction of the barrel can be seen when you bore sight. Bore sighting is done when you look through the bore after removing the bolt from the receiver. 

A rifle that has been zeroed at 100 yards might not be accurate while firing at 300 yards. This is as a result of a bullet drop. Bullet drop increases with distance, and you must compensate by altering the aim point. This is why experienced shooters use a book to keep track of scope adjustment and accuracy at various shooting ranges.

Steps to Zero a Rifle Scope at 100 Yards

Follow these steps to set up your scope at 100 yards.

The first thing you should do is mount your rifle, and place the target at the distance you want to zero. Check that the scope mount if it is properly installed. If you’re using a gun vice, be sure the rifle doesn’t move while you’re shooting.

Look through the scope after setting up the target. Ensure the scope magnification is set to the highest range to create a clear image. Adjust the windage and elevation of the scope turret and ensure that it points the reticle to the target.

When your crosshairs are aligned with the bull’s eye on the target, fire one bullet and look at the impact point. The bullet hole will serve as the starting point for your scope adjustment. Some shooters fire three shots to see whether there would be a shift with each shot.

If your rounds aren’t hitting the target, it might suggest your scope has to be adjusted more. You may need to remove your scope, reinstall, and tighten it in the proper direction. If the rounds miss the target by 2 – 10 inches, make adjustments to the sight. By counting the clicks necessary to adjust a scope, you may exactly measure the degree of adjustment required.

Assuming your rifle scope makes an adjustment of 1/4 inches for each click.  You would need to adjust the elevation and windage by  12 MOA up and 16 MOA right if the bullet hits the target 3 inches below and 4 inches to the left

Take another test shot after adjusting the scope to see where it lands. If you make the necessary modifications after the first shot, the rifle’s accuracy should increase and your shots should be closer to the bull’s eye. If you’re still a few inches off, make smaller changes until your shot is dead center.

Is it possible to zero a scope without shooting?

A boresight can be used to zero a scope without firing. Bore sighting lets you anticipate where the bullets will strike based on the angle and direction the gun barrel points to. Bore sights may be used in three ways.

Firstly, you can make use of a visual bore sight by aligning the sights with the center of your rifle’s barrel. This approach requires more time to fire and may not always perform properly if you go beyond a certain distance.

Second, a laser bore sight can be used. This procedure is simple and quick. The laser is installed into the muzzle of your gun and travels in a straight line. You can use any laser bore sighter that is convenient for you, whether red or green light. The red light bore sighter usually points a red dot on the target. To increase accuracy, make sure you set the scope for proper bullet drop before shooting.

Magnetic boresighting is the third type. It’s not often used, but it’s an excellent technique to zero a scope without firing a shot. Simply connect it to the end of the gun and set its crosshair by looking through the scope.

Can I Sight for a 100 Yard Zero at 25 Yards?

You can zero your rifle scope for 100 yards and shoot at a distance of 25 yards. You may do this by making your impact point lower than your target distance of 25 yards. Typically, a lower correction of .5′′ – 1.5′′ is required.

That is, assuming your shots are hitting the target perfectly. A scope zero that works .5 to 1.5 inches below the target at 25 yards should be accurate at 100 yards.

When Should You Zero Your Long-Range Scope?

A long range zero, such as a 1000-yard zero, is only useful when firing at that distance. If you try to zero at 1,000 yards and then shoot at 100 or 200 yards, your bullet would be totally off target.

Another factor for long range shooting is the elevation adjustment range provided by your scope. If you zero at a longer distance and then fire at 100 yards, you must change your elevation otherwise your shot will be too high. However, the elevation range of your scope may not be adequate to change by that much, and you will still miss your shot.

The same may be said for the reverse case. If you zero at 200 or 300 yards and you intend to fire 1,000 yards, you will not be able to modify your elevation sufficiently to correct for bullet trajectory.  If your target is 1,000 yards away, the bullet drop would be several feet, and most riflescopes do not have that kind of range.

Make certain that you will fire at or near the range at which you have zeroed. If you always shoot between 700 and 1,000 yards, zero for that shooting range.

Leave a Comment

Your email address will not be published.