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Rifle Scope Size: What To Consider

Are you a gun enthusiast looking for the perfect scope that can take your shooting game to the next level? What you need is a scope that will help you hit the bullseye every time! And one of the most important factors to consider when choosing a riflescope is its size.

Now, before you start thinking that size doesn’t matter, let me tell you – it does! The size of your scope can make all the difference between hitting your target with precision or missing it by a mile. But don’t worry; we’re here to guide you through all the factors you need to consider to choose the perfect size of scope.

Choosing a rifle scope can be likened to choosing a partner – you want someone who is just the right fit for you, maybe not too big and not too small, or vice versa. In the same way, you may desire a scope that is perfect for your shooting needs. Whether you’re a long-range shooter or prefer shooting at targets up close, the size of your rifle scope is crucial.

rifle scope size

So, let’s get started and find the perfect size of rifle scope for you!

What is a rifle scope size?

Rifle scope size refers to the physical dimensions of the scope, including the objective lens diameter and overall length and weight. The size of the scope is important because it can significantly impact shooting accuracy. For example, a larger objective lens diameter can allow more light to enter the scope, resulting in a brighter image. However, a heavier scope can impact shooting stability and accuracy. Similarly, the magnification range, reticle type, eye relief, and field of view all play a role in determining the right size of scope for your shooting needs. You can improve your shooting accuracy and precision by choosing the right size of the riflescope.

Note: There is no particular unit for measuring the size of a scope. This is because the size could mean length, width, weight, or any other metric. 

Rifle scope size: what to consider

Choosing the right size of scope is not just about picking a number and going with it. There are several factors that you need to take into consideration to ensure that your rifle scope meets your shooting needs. The factors we’ll discuss in this section determine the sizes of the entire scope (external) or some parts of the scope (internal).

Objective lens Diameter

Objective lens Diameter

The objective lens diameter is a critical factor in determining the size of a rifle scope. The objective lens is the lens at the end of the scope farthest from the shooter and is responsible for gathering light to form an image. The objective lens diameter refers to the size of the lens and is measured in millimeters.

The objective lens diameter plays a crucial role in determining the amount of light that enters the scope. A bigger objective lens will allow more light to enter, resulting in a brighter and clearer image. This feature is important in low light conditions. A larger objective lens diameter can significantly affect target acquisition and accuracy.

However, a larger objective lens diameter also means a heavier and bulkier scope. This can affect shooting stability and accuracy, particularly when shooting for extended periods or when shooting at moving targets. It can also make it more challenging to maneuver the rifle in tight spaces, such as when hunting in densely forested areas.

Choosing the right objective lens diameter depends on your shooting preferences. A larger objective lens diameter may be necessary for long range shooting or night hunting to ensure clear target acquisition. However, a smaller objective lens diameter may be a better option if you prioritize portability and maneuverability.

A 40-50mm objective lens diameter is a good all-around size for most shooting scenarios, providing a good balance between brightness and scope size. However, for specialized shooting scenarios, such as long range shooting, a larger objective lens diameter may be necessary to achieve the required level of accuracy and precision.

In addition, a heavier scope can also affect the balance and feel of the rifle. The added weight can shift the center of gravity, making the rifle feel unwieldy or unbalanced. This can make it more challenging to shoot accurately, particularly when shooting from an unsupported position.

Choosing the right objective lens diameter depends on your needs, and there is no one-size-fits-all solution.

Magnification range

The magnification range is another critical factor to consider when choosing the size of a rifle scope. The magnification power refers to the degree to which the scope can zoom in on a target and is typically expressed as a range of numbers (variable power scope magnification), such as 3-9x or 4-12x. The first number indicates the lowest rifle scope magnification level, while the second is a higher magnification. You can also have a fixed power scope, in which case you’ll have only one magnification power.

The magnification range plays a crucial role in determining the scope’s versatility. A wider magnification range can be useful in various shooting scenarios, from close-range hunting to long-range precision shooting. However, a wider magnification range (4-25x) can also result in a larger and heavier scope, which can affect shooting stability and accuracy.

On the other hand, a narrower rifle scope magnification range (3-9x) can result in a smaller and more lightweight scope, which can be easier to maneuver and shoot accurately. However, it may be less versatile and may not be suitable for all shooting scenarios.

When choosing the magnification range of a rifle scope, it is important to consider the type of shooting you will be doing. If you are shooting at varying distances, a wider magnification range may be necessary to ensure accurate short- and long range targeting. A narrower magnification power may be more appropriate for specialized shooting scenarios, such as close-range hunting.

Reticle Size and Type

The reticle of a rifle scope is the crosshairs or other markings on the scope that are used for aiming at a target. The size and type of reticle can impact shooting accuracy and precision, making it an essential factor to consider when choosing the size of a scope.

The reticle’s size can impact the shooter’s ability to accurately aim at a target. A larger reticle may be easier to see, particularly in low light conditions, but it can also obscure smaller targets at longer distances. A smaller reticle, on the other hand, can provide more precise targeting but may be more difficult to see, particularly in low light conditions.

The type of reticle can also impact shooting accuracy and precision. The types of reticles available include duplex, BDC, and mil-dot reticles. Duplex reticles are a very common type, and they are made of a thin crosshair in the center of the scope with thicker lines on the outer edges, providing a quick and easy aiming point. Mil-dot reticles have markings that allow for range estimation and bullet drop compensation. BDC reticles are meant to compensate for bullet drop at specific distances, making them useful for shooting at longer ranges.

Reticle type

When choosing the reticle size and type, you must consider the type of shooting you will be doing. For example, if you carry out long distance shooting, a mil-dot or BDC reticle may be more appropriate, while a duplex reticle may be more suitable for close-range shooting. It is also important to consider personal preferences and shooting style when choosing the reticle size and type.

Eye Relief

Eye Relief

Alright, let’s talk about eye relief! Now, you might think that eye relief refers to how relieved your eyes feel after a long day of shooting, but that’s not quite it. Eye relief actually refers to the distance between your eye and the scope that allows you to see a clear and full image.

Now, why is eye relief important? Well, if you’re shooting a high-powered rifle, the recoil can be quite powerful. If your eye is too close to the scope, that recoil can cause the scope to smack you right in the face. Ouch! That’s not only painful but can also be dangerous. On the other hand, if your eye is too far away from the scope, you won’t be able to see a clear and full image, which can impact your shooting accuracy.

So, finding the right (size) eye relief is crucial for both your comfort and shooting accuracy. Typically, the recommended eye relief for most rifle scopes is around 3-4 inches, but this can vary depending on the type of rifle and shooting style.

Now, how do you find the right eye relief for you? Well, it’s all about experimentation. You’ll need to try different eye relief distances to see which is most comfortable for you while still allowing you to see a clear and full image. It’s important to remember that everyone’s eyes are different, so what works for one person may not work for another.

One thing to remember when considering eye relief is the type of shooting you’ll be doing. If you’re shooting in a prone position, you’ll want a longer eye relief distance to accommodate the position of your head and the rifle. Conversely, if you’re shooting in a standing position, you may be able to get away with a shorter eye relief distance.

It’s also worth noting that some rifle scopes have variable eye relief, meaning that the distance can change depending on the magnification level. This can be beneficial if you’re shooting at different ranges and need to adjust your eye relief accordingly.

In addition to the physical distance between your eye and the scope, it’s also important to consider the shape of the eyepiece. Some rifle scopes have eyepieces that are shaped to make it easier to get a consistent and comfortable eye relief distance. This can be particularly useful for shooters who wear glasses or have other vision impairments.

Field of View 

Alright, let’s talk about the field of view! Field of view refers to the area of your target that you can see through the scope, and it’s important to consider when choosing a rifle scope.

So, why does the field of view matter? Well, a wider field of view means you can see more of your target, making it easier to track and shoot moving targets. It also allows you to see any potential obstructions or obstacles that may impact your shot. On the other hand, a narrower field of view means you’ll have to move the rifle more to track your target, which can be slower and less efficient.

The field of view is typically measured in feet at a certain distance, such as 100 yards. A wider field of view will have a larger number, while a narrower field of view will have a smaller number. It’s important to note that the field of view can vary depending on the magnification level of the scope, so make sure to check the specs for both the minimum and maximum magnification levels.

In addition to the numerical measurement, it’s important to consider the shape of the field of view. Some scopes have a circular field of view, while others are rectangular. The shape can impact your ability to see your target, especially if it’s moving or if you’re shooting in a specific direction.

So, when choosing a rifle scope, make sure to consider the size of the view to ensure you’re getting the widest view possible. It can make a big difference in your shooting accuracy and efficiency, and can help you take down those moving targets with ease!

Parallax Adjustment

Parallax adjustment is a feature on many riflescopes that can help you achieve greater accuracy by eliminating an optical illusion.

Parallax is the apparent shift in the position of your reticle in relation to your target. This occurs when your eye is not perfectly aligned with the scope, leading to missed shots and decreased accuracy. Parallax adjustment is a way to correct this by adjusting the position of the reticle in relation to the target.

So, how does it work? Well, parallax adjustment typically involves adjusting a small knob or dial on the side of your scope (this particular knob adds to the overall size of the scope). The knob changes the position of the reticle, which can help eliminate parallax. Some scopes have a fixed parallax adjustment, while others are adjustable based on the distance to your target.

It’s important to note that parallax adjustment is most effective at longer ranges, typically beyond 100 yards. At shorter ranges, the effect of parallax is typically negligible. However, if you’re shooting at longer distances, parallax can have a significant impact on your accuracy, so it’s important to consider this feature when choosing a scope.

One thing to keep in mind is that parallax adjustment can add some complexity to your shooting process. You’ll need to adjust the knob or dial based on the distance to your target, which can take some practice to get right. However, once you’ve mastered the adjustment process, you’ll be able to achieve greater accuracy and hit those targets with precision.

Scope Tube Diameter

The tube diameter can impact the overall size and performance of your scope. A larger scope tube diameter can provide more room for the internal components of the scope, allowing for more light transmission and a greater adjustment range. But, a larger tube diameter can also make the scope heavier and bulkier.

On the other hand, a smaller tube diameter can provide a more compact and lightweight scope, but it may not have the same level of performance as a larger tube diameter scope.

It’s important to find the right balance between tube diameter and overall size when choosing a scope. And remember, just like with a sports car, sometimes the fanciest and biggest option isn’t always the best choice for everyone.

Turret size

Turrets may sound like something out of a sci-fi movie, but they’re actually an important part of a rifle scope! Turrets are the little knobs on the top and sides of the scope that allow you to adjust your aim.

The size of the turrets can impact the overall size and weight of the scope. Bigger turrets can be easier to adjust, but they can also make the scope bulkier and heavier. It’s kind of like choosing a backpack for a camping trip: a bigger backpack can carry more gear, but it can also be heavier.

However, the size of the turrets is also important for accuracy. Larger turrets can provide more precise adjustments, which is especially important for long-range shooting. So, it’s a bit of a trade-off between ease of use and accuracy.

Some scopes also have exposed turrets, which can make them easier to adjust quickly. However, exposed turrets can also be more vulnerable to damage and may require extra care and maintenance.

When choosing a scope, consider the size and location of the turrets and how they fit into your shooting needs. A larger, more precise turret may be worth the extra weight and size if you’re shooting at longer distances, while a smaller, more compact turret may be a better choice for hunting or other fast-paced shooting scenarios.

Scope Size Recommendation 

Small to Medium-Sized Scopes for Close-Range Shooting

If you’re going to shoot at targets that are relatively close to you, like when you’re hunting in the woods or shooting at a shooting range with shorter distances, then a small to medium-sized scope would be a good choice. These scopes are more compact and lighter, making it easier to move around quickly and aim at nearby targets. They work well for quick shots and in situations where you don’t need to see very far.

Medium to Large-Sized Scopes for Long-Range Precision

On the other hand, if you plan to shoot at targets that are far away, like when you’re doing long-range shooting or hunting in open fields, then a medium to large-sized scope would be more suitable. These scopes have larger lenses, which help gather more light and provide clearer images at longer distances. They allow you to zoom in on your target and make precise shots, ensuring you hit the bullseye even from far away.

Shooting Environment

The shooting environment, or the place where you’ll be using your rifle, is important to think about when choosing a scope. Different places require different sizes of scopes for the best performance.

Dense Forests or Close-Quarters Shooting

If you often shoot in places like dense forests or when you’re up close to your target, you need a scope that is small, lightweight, and easy to handle. This kind of scope will help you quickly aim and shoot at nearby targets because it won’t slow you down or get in the way. 

Long-Range Shooting or Open Fields:

If you do a lot of shooting from far away or in open areas, you need a different type of scope. A larger scope with a bigger lens at the front is better for this situation. It helps you see your targets clearly even from a distance. Also, a scope with higher magnification, which is like a zoom feature, is necessary to spot faraway targets and make accurate shots. 

Balancing Size and Weight

When it comes to riflescopes, bigger lenses and more zoom power can make your scope work better, especially in certain situations. But, there’s a trade-off. These bigger and better features also make the scope heavier and bigger, which might not be so good. So, finding the right balance between having a powerful scope and making sure it’s not too heavy or bulky is essential. If your scope is too heavy, it can make your rifle harder to carry around, and it might get tiring to shoot for a long time. 

The trick is to choose a scope that fits well with the type of shooting you do the most. If you often shoot in situations where you need to move a lot or carry your rifle for a long time, then a smaller and lighter scope might be a better fit. On the other hand, if you do a lot of shooting at long distances, then you might need a bigger scope with more zoom to see faraway targets clearly. In the end, it’s all about finding the right balance that matches your shooting style and makes your shooting experience comfortable and enjoyable. 

Budget and Compatibility

Budget Considerations

Riflescopes come in different price ranges. The price can be influenced by the size and the features they have. The bigger the objective lens and the more advanced the features, the more expensive the scope might be. So, if you have a specific budget in mind, it’s essential to consider the trade-offs between size, features, and cost.

If you’re on a tight budget, you might need to make some hard choices. You could go for a smaller scope or one with fewer fancy features, but it can still work well for your shooting needs. Remember that the right scope for you depends on what you plan to use it for. So, if you mainly shoot at close distances, a more basic and affordable scope might do the job just fine.

Compatibility with Mounts and Firearms

Before you buy a rifle scope, you need to make sure it fits your firearm properly. You have to check the size of the scope’s tube and make sure it matches with the mounts on your rifle. If they don’t fit together, the scope won’t work as it should, and that’s no good! Also, consider the height of the scope and how it lines up with your eyes when you’re shooting. You want it to feel comfortable and natural when you look through the scope. If it’s not the right height for you, it might be awkward to use, and that can mess up your shooting accuracy.

So, remember to check that the scope fits well with your rifle and that it feels right when you’re aiming. This way, you can get the best out of your rifle and scope combination, making your shooting experience more enjoyable and successful!


What role does scope size play in shooting accuracy?

Scope size plays a crucial role in shooting accuracy. The size of the scope affects how much light enters the scope and how clear your target appears. A larger scope with a bigger objective lens allows more light to come in, leading to a brighter and clearer image. This is especially important in low-light conditions, such as during dawn or dusk.

Moreover, a larger scope with higher magnification can help you see far targets more clearly. However, it’s important to strike a balance between scope size and comfort. If the scope is too heavy or bulky, it might become challenging to handle, which can negatively impact your shooting.

How does magnification power affect the size of a scope?

Magnification power refers to how much the scope can zoom in on a target. Higher magnification means the scope can make distant objects appear closer. Magnification power can impact the size of a rifle scope because scopes with more magnification might need larger lenses and more complex internal components to maintain image clarity. A scope with a higher magnification range is usually larger and heavier compared to a scope with a lower magnification. 

What is the significance of objective lens diameter in scope size?

The objective lens diameter is an essential factor in determining the size of a riflescope. The objective lens is the one farthest from the shooter, and its size impacts how much light can enter the scope. A larger objective lens diameter allows more light, resulting in a brighter image and improved visibility, especially in low-light conditions.

However, a larger objective lens also means a larger and heavier scope. While this can enhance image quality, it may affect shooting stability and maneuverability, especially in tight spaces.

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