Best Crossbow Scope Reviews – What’s on the market in 2022

 

Every experienced bow-hunter is aware of the importance of using the best crossbow scope possible. Owning the highest performance crossbow and having exceptional shooting skills is just some pieces of the puzzle. In order to reach your full potential and be an accomplished shooter, you need every help you can get. A crappy scope would jeopardise your efforts, so you need to make sure that you spare some bucks for a better one that will enhance your aiming.

Despite the fact that most crossbow packages come with built in scopes, more often than not they are lacking in quality and a third party option can make a significant difference to your hunting experience.

But, how will our crossbow scope reviews help you? Having tried and reviewed a lot of scopes ourselves, we want to share our “wisdom” with you, our fellow hunters, and provide you with the right scope for both those looking for the highest quality and those who are on a budget.

Best Crossbow Scope Reviews for 2022

 

1. TenPoint Crossbows Rangemaster PRO

Main advantage

Probably the most important benefit that you will get if you decide to go for this alternative is that it comes with fully multi-coated 1.5 to 5x optics. On the one hand, you get a lot of versatility because you are able to adjust the zoom as per your needs. On the other, it’s worth noting that fully multi-coated optical components are always top-quality, so the images you’re going to look at are definitely going to be bright and clear.

Main disadvantage

There used to be a red ring around the lens on older versions, and that made it impossible for the hunter to go unnoticed by the prey. Fortunately, the manufacturing brand has removed it so as to make it as user-friendly as possible, especially for your particular purposes.

Versatility at its best

As we have mentioned in the introduction, the best thing about this alternative is that you will be able to make the most of it in a host of situations. More often than not, scopes come with a fixed magnification, which doesn’t give you the capability to work your way around different hunting circumstances.

This is not the case with the TenPoint Crossbows HCA-09811, however, since it comes with 1.5 to 5x optics. Merely adjust the scope as per your liking or depending on what your momentary hunting situation calls for.

Lightweight and durable

From the information that we have gathered about this option, its tube is made out of aluminum, which means that it doesn’t weigh too much and it won’t be too heavy along with the crossbow as you use it. The tube measures just 8.25 inches, so that’s another thing not to worry about. It’s pretty compact, but most of the reviews we’ve gone through in this sense actually praise its ruggedness and ability to last for as long as possible.

Optics

When it comes to crossbow scopes, you have to pay extreme attention to the optical components that they come with. Otherwise, your whole experience might be ruined on account of you not being able to spot your target as you should. Luckily for you, this particular model comes with fully multi-coated optics.

What does all of this mean? The number of coatings on the lenses of any optical instrument matters a lot, because they can make the difference between a quality unit that you need and will enjoy using and one that will disappoint you because it won’t have great performance. Thanks to the optics that it comes with, the TenPoint Crossbows HCA-09811 is capable of offering you crisp and clear pictures.

That, in turn, means that, since you are going to be able to see clearly, you are also going to be capable of spotting your targets with more efficiency. What this spotting scope does is actually spot your potential prey and it’s really good at doing that.

Field of view

We couldn’t leave out the field of view boasted by this alternative, and that’s because it’s 50 feet at 100 yards. With that much width, you will be able to track your targets even as they move. Besides, since you already have the advantage of excellent optics, you might want to know that the resolution remains great even when the scope is used at maximum magnification.

Usability

If you have tried out other crossbow scopes, you undoubtedly won’t find it hard to use this particular one. Based on the feedback provided by some of the hunters who reviewed the product, it seems that it is easy to set up on the weapon of your choice. On top of everything, you can even make the most of it by utilizing it with two or more crossbows, especially since this one is a great fit for bolts that fly between 275 and 425 FPS. Besides, it comes with comfortable eye relief, so that’s one less thing to worry about.

PROS:

• Versatile 1.5 to 5x optics
• Fully multi-coated optical elements
• Excellent light transmission
• Markers from 20 to 60 yards

CONS:

• With older versions, there used to be a red ring around the lens, which made it easy for the prey to spot the hunters. Fortunately, this has been removed.

Summary

You might want to know that TenPoint also makes crossbows, and that’s one of the reasons why this product actually meets and even exceeds the expectations of many bow hunters. It’s a quality piece of equipment that will help you increase your hunting performance, and its variable zoom is definitely something you wouldn’t encounter in other options.

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2. TenPoint Pro View 2

Main advantage

The most important benefit you’ll be getting if you decide to opt for the TenPoint Crossbows HCA-097-II crossbow scope is its optics quality. The lenses are fully multi-coated, which means that this alternative is a winner in terms of light transmission, and that’s always something to consider when you’re hunting in darker conditions such as at dawn or dusk. We’ll further detail the quality of the optical components in the sections below.

Main disadvantage

We were unable to find any negative scope reviews with regard to this particular model, but there have been some mentions of the rings. Apparently, the ones that come shipped with the model when you buy it seem to be rather cheaply made, which obviously bothers many hunters.

Compact design

Nobody likes carrying heavy hunting gear around, especially because you already have the weight of your weapon of choice to handle. There’s no point in increasing its overall weight to make you unstable while holding it by adding a hefty scope to it.

Fortunately, that is something the TenPoint Crossbows HCA-097-II is particularly good at preventing, and that’s all thanks to its compact design. It measures just 8.5 inches, and the 32mm tube is reasonably lightweight, especially based on what the people that have used it in the past have had to say about it.

Optics

One thing that you definitely do not have to worry about is the quality of the optical components that this particular crossbow scope comes fitted with. They are fully multi-coated, which means that they are more than capable of transmitting light as they should, even when you are hunting your prey in somewhat darker conditions than the usual ones.

In case you didn’t know, fully multi-coated lenses are the best when it comes to ensuring brightness transmission, so obviously, this choice comes with top-notch optics that can take your hunting to a new level by providing you with accuracy.

Easy to set up, easy to sight in

Most of the information that we have stumbled upon notes that this device is considerably easier to mount compared to others we’ve found. It’s also worth adding that the rings are included with your purchase, so what you see is what you actually get, in this case.

Sighting in the scope can be done almost effortlessly, based on what many hunters had to say about it. Its user-friendly design makes it possible for this crossbow scope to be used by almost anyone, as long as that person is aware of the velocity of their weapon. This device is equipped with a simple focus ring on the back, and that makes it possible for you to see the cross hairs and dots clearly. If you wear glasses, you will undoubtedly find this feature particularly helpful.

You can also perform a simple adjustment on the side of the scope and get the dots illuminated with red or green light. Some buyers recommend avoiding using the highest setting right off the bat, though, so it might be a good idea to start with the minimum one and only then perform other adjustments as the daylight gets stronger.

Magnification

This product comes with a 3x fixed magnification. On the one hand, that might seem like a disadvantage because you have no means of adjusting it depending on your momentary necessities, which means that you’ll partly have to ‘zoom in’ and ‘zoom out’ using your own two feet.

However, this type of magnification is the one commonly featured by most spotting scopes and since you won’t be fiddling with any parts, you will also expand the life of the product and be able to enjoy it for as many future hunting seasons as possible. Some hunters even note that it is higher than what they usually prefer.

PROS:

• Great fully multi-coated optical components
• Excellent light transmission
• 3×32 optics
• 3 reticle options you can choose from
• It comes with the rings included

CONS:

• Some users say that the rings seem pretty cheap

Summary

There are many reasons to consider this particular crossbow scope. It’s easy to install, it provides you with the accuracy you need to get a clean kill, and the optics are fully multi-coated and offer you excellent light transmission. The images are clear and bright, so you have a perfect sight to get your next target and strike it down. Mounting and adjusting the scope can be done effortlessly, and the compact design definitely helps since you won’t find it too hard to carry or use on your bow.

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3. Excalibur Crossbow Dead-Zone 1952

Main advantage

If you are in the market for an affordable crossbow scope, and you haven’t tried any other models before, perhaps the Excalibur Dead-Zone 1952 is a feasible choice for you. It doesn’t come with the same high-end specs of some of the more expensive options out there, but it is very easy to sight in and will help you see your target conveniently and effectively even in low-lighting situations.

Main disadvantage

Although it is a highly usable alternative, there is one thing that you have to bear in mind with this budget-friendly unit. This consists of the fact that it is outfitted with multi-coated lenses. In case you didn’t know, the best in this line of products are lenses that are fully multi-coated, so these might be able to transmit light a little less adequately compared to premium scopes.

Compatibility

We’ll get it right out of the way because you might want to know off the bat whether this scope makes a good choice for your particular bow. From the information we have found in this regard, the Excalibur Dead-Zone is compatible with bows that shoot bolts at velocities ranging from 300 to 410 FPS.

Portability

The weight and size of a crossbow scope can make a difference when it comes to user experience, and most archers will be aware of this aspect. Fortunately, this one isn’t too large since it measures 10.8 by 6 by 2 inches. As for the weight, it weighs less than one pound, so it won’t hang too heavy on your bow.

The compact design of the product is an advantage in itself as you will be able to transport it effortlessly. Even if you mount it and dismount it time and again, you can safely carry it in a case or pouch as per your momentary requirements.

Optics

It’s pretty difficult to tell whether the optical components of this scope are high-quality or not. Although most of the consumer reports received by this particular model are favorable in this sense, we haven’t found a lot of information that could sustain the statements.

Based on what we came across while browsing through the info supplied by the brand, the optical parts of this scope are multi-coated, which basically explains its low cost. Compared to fully multi-coated optical components, multi-coated ones don’t have the same superior capability to gather light and render the images that you will look at bright and clear. However, compared to optics that are simply coated, these are good enough to meet your needs, especially if you are only beginning your archery journey.

Mounting

First off, you need to make sure that the crossbow is not cocked. Safe handling procedures are highly recommended at all times.

Start by attaching the rings to the scope mounting area, and then separate the bottom portion from the tops. Position the scope in the cradles formed by the bottom parts of the rings, and then replace the tops, but do not tighten just yet. Proceed by pushing the scope as far as it can go, and then rotate it so as to end up with the elevation turret on top. Either bench rest or shoulder the crossbow and then pull the scope toward you (back) until you can look at the whole field of view. Check whether the horizontal components are aligned with the limbs.

Wrap up the mounting process by tightening the ring tops only after you have adequately positioned the scope, and the reticle is aligned with the limbs.

Other features

It’s good to know that, unlike many of its competitors, this scope doesn’t just come all on its own. It is accompanied by 1-inch rings, something you might fail to find in many other alternatives, a lens cloth, an Allen key, as well as lens caps which will assist you in extending the life of the product for as long as possible. The reticle is illuminated in red and green, and the scope has an adjustable multiplex crosshair system which will assist you in improving your hunting performance as best as possible.

PROS:

• Way more affordable than similar choices
• Decent fully coated optical components
• Versatile, since it is a variable multi-reticle scope
• Designed for crossbows that shoot from 300 to 410 FPS

CONS:

• The light transmission is that of fully coated optics

Summary

This is a decent scope for the money, but we would advise you to keep your expectations realistic seeing how this one comes with multi-coated optical components instead of fully multi-coated ones. The set does include a limited number of accessories with which you can get the most out of your bowhunting experience, but we would advise you to give it a try especially if you are a complete rookie and you don’t know what scope to pick.

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4. UTG 4×32 1”

Main advantage

Probably the most notable advantage you’ll be able to benefit from if you decide to go for the Leapers UTG scope is that it provides you with excellent illumination. It boasts a 4x magnification and the clarity and resolution are excellent, especially considering that this optical instrument definitely doesn’t cost a fortune, like many of its competitors.

Main disadvantage

The reticle has all five lines crossing the diameter of the eyepiece, which can be considered a downside. Based on some of the consumer reports that we have analyzed, it seems that a pyramid style of lines would have been a lot better. Some buyers have received defective units, but if that happens, you can swiftly get in touch with the brand’s customer support and get a replacement.

Optics quality

While most of the bow hunters’ opinions we have come across are favorable in this sense, we couldn’t really tell whether the optics of this particular device are multi-coated or fully multi-coated. The brand only states that it uses broadband lens coating. However, based on the excellent user experience when it comes to the light transmission capabilities of the scope, it’s safe to assume that the optics are, indeed, fully multi-coated.

Fully multi-coated optical components are the best when it comes to providing you with the brightness you need, especially when you’re doing your hunting in darker environments or at dusk or dawn.

Light gathering capabilities

The scope comes with a 32mm objective lens that does a great job when it comes to providing you with the light you need to see your targets exactly how you’re supposed to. The view in low-light conditions is excellent, and besides, the illuminated reticle is made with amazing brightness settings.

You can set the illumination to be either green or red, and you have as many as 5 brightness settings of each color to select from. Turning the illumination entirely can be done for the black reticle, therefore allowing you to hunt during the day.

Battery

This scope works with a CR1620 battery, and fortunately, you get one included in the deal. If you plan on doing a lot of low-light hunting, we would advise you to purchase one or even two more such batteries so that you can always use your scope as per your needs.

Although the unit offers you the benefits of an excellent battery life, the power consumption can be increased by inclement weather, for example, and a variety of other factors.

Durability

The UTG 4×32 crossbow scope is nitrogen-purged, which means that you’re going to spend your precious pennies on a unit that’s fog proof, but also shockproof and rainproof. Of course, it’s not entirely waterproof, but it does stand the abuse of rougher environments, so it won’t let you down when you need it the most. Unless you plan to submerge it in water entirely, there’s no chance you’re going to damage this optical instrument too soon.

We’ve also come across several reports from hunters who say that they’ve dropped the scope on the floor several times and that it didn’t suffer any damage whatsoever.

Mounting and sighting in the scope

Another great advantage of considering this option is that it comes with its own rings, so you don’t have to worry about anything when it comes to mounting it on your scope. Your crossbow does have to come with a Picatinny or Weaver rail, though, so keep that in mind.

Is this scope easy or hard to sight in? It takes just a couple of seconds to get the procedure done as long as you use the zero-reset function to align the markings after zeroing the optical device. It is very difficult, if not impossible for anything to knock off your scope once you’ve sighted it in.

PROS:

• Great light transmission for a 32mm lens
• The product comes with the rings you need
• It’s nitrogen purged so it’s fog proof
• 3.8-inch eye relief

CONS:

• The reticle has all five lines crossing the diameter of the eyepiece

Summary

This 4x crossbow scope comes with a 32mm objective lens and can offer you excellent clarity and resolution, which is why it is worth trying out. The rings are included in the box, and there’s a 3.8-inch relief that you can benefit from. It’s also nitrogen-purged, so it’s rainproof and fog proof, and once you sight it in, it’s almost impossible for anything to knock it off. The reticle can be considered an inconvenience, though, especially if you’re only used to working with pyramid-style reticles.

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5. TRUGLO 4X32 Camo

Main advantage

If you are looking for an affordable scope that is still capable of providing you with the performance you need in the field, you might want to consider this 4×32 model from TRUGLO. It is designed for accuracy and durability, and it also comes with a limited lifetime warranty. This scope is also easy to sight in and comes with a special compensating reticle that will help ensure every shot is consistently accurate.

Main disadvantage

Even though this scope is designed to be compatible with most crossbows, some consumers have noted that it can be difficult to mount. If a wrench or other tool is not used to tighten it down securely, the scope can become loose and potentially fall off. While this is not always an issue, it is something you might want to consider depending on the make and model of your crossbow.

Durable

Not only does this crossbow scope from TRUGLO comes with a durable construction, it is also backed by a limited lifetime warranty. This ensures that you will consistently get the same great performance for the life of the crossbow scope. The single tube is constructed from the same aluminum that is used in aircraft so you know that it will last for years. The leaf spring for adjustments is also designed for durability and is resistant to bending or breaking.

The scope also comes with a professional matte finish that won’t reflect any light that might startle nearby prey. Resistant to scratches and designed to be used in almost any weather, this affordable scope will easily make it through the whole season with you.

Quality optics

With its low price, you might think that you are sacrificing optic quality, but this is not the case with the TRUGLO 4×32 scope. The lenses are fully coated to allow plenty of light through and to ensure images are crisp and clear. The coating also helps to alleviate any problems with fog or moisture which can cause lenses to cloud over in the early morning hours.

You will appreciate the 4-inch eye relief that makes it easy to see a target at a glance, and the rubber guard helps to prevent any painful bumps. With 4×32 magnification, you can easily see distant targets and the reticle ensures you know exactly where to aim to make a humane killing shot. The reticle can be easily adjusted for range and trajectory, which makes this scope ideal for firing down on targets from a tree stand.

Ease of use

This crossbow scope is designed to be easy to use, even when you are in the field. It can be easily mounted onto almost any crossbow, and you don’t need to worry about following any complicated instructions. Simply tighten the scope down and you are ready to go.

When you need to make adjustments for wind or elevation you won’t need to grab any additional tools. There is a small leaf spring that you can easily move with your finger so you will always know the right trajectory for your arrow to follow depending on the range. When you know the path your arrow should take it is easier to hit the target exactly where you want to. Since it is also designed to hold at zero you might not have to make complicated adjustments that might distract you from the hunt.

PROS:

• Reticle sized for deer
• Field of view
• Camo Finish

CONS:

• Missing illumination
• Rings not suitable for every mount

Summary

This affordable crossbow scope is designed to be durable and to make it easier for you to see targets at a distance. It is water and fog proof so you don’t have to worry about a loss of visibility, and since the lenses are fully coated images will always appear bright and clear. You will also appreciate how easy it is to sight in and adjust, especially in the field. While this might not be the highest quality scope, it is an excellent choice for your money.

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How to choose the right scope for your crossbow

When you are ready to add a scope to your crossbow there are a few aspects to consider, and the following tips will help you narrow down your choices so you can make a smart buying decision.

Size

Crossbow scopes can vary in size, and you want to choose one that is smaller enough to easily carry with the rest of your gear. The scope should also weigh less than one pound so it does not throw off the balance of the bow. Heavier scopes can not only make the bow difficult to hold, it can also make it almost impossible to aim your shots accurately. Most experts recommend choosing a scope with a wide lens so you can easily see any targets, but still comes in a lightweight and compact design.

Magnification and optics

While magnification is important since you want the scope to be powerful enough to clearly see images at a distance, you also want to consider the quality of the optic lens. Even the most powerful scope will be useless if the lens isn’t capable of producing crisp and bright images. Crossbow scopes with fully multi-coated lenses are designed to allow plenty of light to flow through so you will be able to clearly see your target regardless of the distance.

You also want to make sure that the scope is nitrogen filled since this will prevent early morning dew and fog from clouding the lens. If you are not able to use the scope anytime you need to it can quickly become a waste of money. This is why it is worth it to take a few extra minutes to ensure the scope is moisture and fogproof.

Being able to compensate for range is always an advantage, and most scopes come with a reticle. These convenient markers can make it easier for you to make an accurate shot regardless of the distance or elevation. The field of view is also important, especially if you don’t want to miss seeing a potential target. Wider lenses will give you an improved field of view, but it is important to remember to consider the overall weight of the scope. Some hunters only worry about this when they are hunting deer, but it can also improve your chances of hitting varmints and small game.

Durable and easy to use

Most crossbow scopes are designed to be easy to mount, but it is still something that you want to consider. You also want it to be easy to calibrate or adjust so you can concentrate on the target and not on the scope. Scopes that allow you to calibrate for elevation and wind speed without the use of a tool are generally preferred over other models. These crossbow scopes typically come with small dials that make adjustments a breeze. As the dials are turned you will hear an audible “click” which is designed to help you keep track of the adjustments.

While accuracy and ease of use are important, you also want the scope to be designed to last. Crossbows and scopes can take a lot of abuse in the field, which is why you want to make sure that it comes with a durable construction. The mounting rings should be firmly attached and resistant to everyday wear and tear, and you want the casing to be able to protect the scope against occasional drops and being banged around with the rest of your gear. For added protection and durability some crossbow scopes also come with a sturdy storage case, which is also convenient when you are traveling.

Why You Should Use a Quality Crossbow Scope

While some hunters can’t imagine using their crossbows without a scope, others might wonder if it is really necessary. Not even the most powerful scope will make a crossbow accurate at long distance shots over 50 yards, which makes some hunters wonder why they need to spend the extra money on one. While a scope won’t make your crossbow as powerful or accurate as a rifle at long-distance shooting, there are still a few excellent reasons why it makes sense to use one.

Better Accuracy

Even when you are aiming and firing at targets that are only 10 or 20 yards away, accuracy can still be an issue. When you are shooting arrows at paper or bag targets an occasional miss is usually an annoyance, but out in the field, it can leave an animal wounded and in unnecessary pain. While many hunters choose to use a bow for the challenge it can present, they still want to always be able to make a humane killing shot. This often requires the use of a scope that will clearly show hunters exactly where they need their arrow to go.

A quality crossbow scope will bring the target into view so you can clearly see every detail. With the target appearing like it is right in front of you it is easier to see exactly where you need to send the arrow. Scopes can usually be adjusted to take into account the distance to the target, which also takes all of the guesswork out of deciding where you need to point your bow.

Arrow placement

If you have ever marveled at someone’s ability to have all of their arrows grouped in the target, chances are they had a little help from a quality crossbow scope. Along with helping to improve accuracy, a scope can also make it easier for you to group your shots. When you can consistently send your arrows to the same spot you know that your bow is balanced and performing at optimal levels, which is something that every archer should know.

Archery tournaments often require participants to group their shots, and a crossbow scope can be an invaluable tool during practice sessions. Some tournaments will even let you keep the scope mounted on your crossbow during the competition.

Range

Hunters and even target shooters can spend hours talking about range, even though most crossbows are only accurate up to 60 yards or less. The range not only refers to the distance to the target, it can also take into account the elevation. This is extremely important to consider when you are hunting from a tree stand or firing at targets in hilly locations.

A quality crossbow scope will bring distant targets clearly into view so you can see where you need to aim. Being able to make adjustments for elevation will ensure that your arrow doesn’t drop before it hits the target or overshoot the area you were aiming for. These constant misses are not only frustrating, but it can also result in lost arrows which can be expensive to replace. The noise of the arrow can also startle your target, along with any other nearby game in the area making it a disappointing hunting trip.

Some additional things to consider before buying a top crossbow scope

When purchasing a crossbow scope, there are several main factors you should consider. There are a lot of major and minor considerations when buying this equipment. First, we will take a look at the major items to consider. Obviously, look at your budget and how much you can take from your savings accounts. Some scopes can be bought for less than $70, while some run well over $150. You want to be sure that you spend as much as you can, without breaking your budget. Second, you want to look at the size of the lens that you want for your scope. The larger the lens, the higher level of power you will get. They also translate to larger viewing areas. Next, look at the power and settings of the scope. You want to be able to use your scope and quickly adjust it easily. The more intuitive your adjustment options are, the better and faster you will be able to acquire your target.

There are tons of options available, so when you pick your scope, make sure you choose one that helps you aim, acquire your target, and can stand the test of time. The best crossbow scopes are light and rugged, with great lenses and optical quality. The image quality is absolutely vital, as this is the reason you are buying the scope. The more light that enters the eyepiece, the shaper your resolution will be and more accurate your shot will be. Lens coatings reduce reflection, which causes glare. You should buy a lens that has at least a single coating on it.

Furthermore, check to make sure your scope is fogproof and waterproof. This will save you headaches and repair costs in the future, not to mention the higher quality shots you’ll make. Finally, make sure that the scope warranty gives you solid coverage. Manufacturers often give lifetime warranties on their products. There is a lot of competition out there, so this is a major consideration as well. If a company is willing to replace your product if it fails, then that can save you hundreds of dollars right there. The bottom line here is to use common sense. As long as you stick with the brands with good reputations, you will probably be happy with your new scope and the shooting experience it gives you.

In order to make the best possible decision you have to answer these questions first:

• What will I use my scope for? Competition shooting, General target shooting, Hunting,  or some combination of the 3.
• What is the intended range of my targets? 20 yards, 20 – 60 yards, or over 60 yards.
• What are my preferences for Magnification, Reticle Type, Field of View, and other technical adjustments?

Some terms you should get familiar with in order to choose the best crossbow scope

Magnification

Magnification is one of the basic scope characteristics.  It measures how many times better you can see an object than with your naked eye.  Some rifle scopes offer a range of magnification, for instance anywhere from 3x to 9x.

Field of View

Field of View is the actual width of your scope’s sight picture at a specific distance. For example, at a range of 200 yards, a scope can give you a sight picture that is 20 feet wide.

Field-of-view is a function of both magnification and the focal lengths of the lenses. A key point to keep in mind is that the higher your magnification is, the narrower the field of view is.

Stray Light

When light enters the scope and reflects off of the metal, it reduces the image quality of the target.  This is why you want to find a scope that has interior coating, to prevent reflection off of the metal,.

Eye Relief

Eye relief is simply the distance between your shooting eye and your eyepiece lens. If your eye relief is too small, there is a risk of hitting your eye with the eyepiece when your crossbow releases an arrow.

A general rule of thumb is:  higher magnification and field-of-view equals shorter eye relief.

Exit Pupil

This is a measure of the amount of light that reaches your shooting eye.

Length

Length is straightforward.  It measures your crossbow scope, from the leading edge of the objective lens to the back edge of the eyepiece.  Longer models tend to have greater magnification.  However, some shooters prefer shorter scopes for their weight and smaller profiles.

Center Tube Diameter

Your scope’s center tube diameter affects its durability.  It also determines what size rings and base you need for mounting, as well.