Riflescope Buying Guide: How to Choose Best One

Riflescope Buying Guide, A complete A to Z information about riflescopes and red dot sights for firearms owners.

Most firearm owners use some kind of sighting scope on their guns. Because using a riflescope or sight on your firearms not only gives you precision and accuracy in your shooting but also eliminates the complexity of lining up iron sights.

These scopes enable you to shoot in low-light conditions. You can also view your target more clearly and it increases the chance of hitting the target.

We’ve broken down this Riflescope Buying Guide into three parts. What to look for in the riflescope, Types of scope, and their Brands.

In this way, you will not only learn about the different types of rifle scopes but also understand exactly what you should address before picking a scope for your rifle.

Let’s have a closer look at several important items in this Riflescope Buying Guide that you should take into consideration when looking for the best rifle optics.

A Complete Riflescope Buying Guide

What to Look for in the Riflescope

It is quite obvious that choosing the best rifle scope is not an easy job to do. If you don’t know what variables have to be taken into consideration while picking the best scope for your firearm then you have stepped into the right place.

In this Riflescope Buying Guide, we will try our best to give you an outline of the most important factors that you should keep in your mind while choosing a scope for your rifle.

Here are some important things that we want you to read in this Riflescope Buying Guide before you hit the gun store.

  • Magnification Power
  • Objective Lens
  • Ocular Lens
  • Main Tube of the Scope
  • Exit Pupil
  • Field of View
  • Lens Coatings
  • Reticles
  • Focal Plane
  • Eye Relief
  • Parallax Adjustment
  • Eye Piece
  • Turrets
  • Waterproof and Fogproof
  • Windage and Elevation

Magnification Power

Generally, a riflescope is expressed in a series of numbers such as 4-16×42 or 4×32 scope.

4-16×42 is a variable magnification scope because you can vary the magnification of the scope from four to sixteen, stopping anywhere between four and sixteen.

4×32 is a fixed magnification scope because the magnification power of the scope is fixed at 4x and you can not adjust the magnification.

4x means that the image you see through the lens appears four times (4X) closer than it does with your naked eye.

Similarly, 16x means that the image you see through the lens appears sixteen times (16x) closer than it does with your naked eye.

In the above two examples, 42 and 32 are the diameter of the objective lens expressed in millimeters.

Most of the scopes available on the market have variable magnification power, such as the 4-16× mentioned above.

The larger the magnification range, the more versatile your scope is. The higher magnification scopes allow you to see further and in more detail.

Some hunters prefer fixed power rifle scopes while others have a distinct preference for variable power rifle scopes according to their needs.

Objective Lens

The lens located farthest from the eye of the shooter when seeing through the scope tube is Objective Lens.

The second number used in rifle scope identification tells you about the objective lens diameter expressed in millimeters such as 4×32.

In this example, the objective lens diameter is 32mm. The larger the Objective Lens diameter is, the more useable light it will transmit through the Scope Tube to the Ocular Lens for clearer images even in low-light conditions.

However, it’s important to consider that a larger objective lens diameter makes for a larger and heavier riflescope.

For maximum brightness, the lenses of the scope should be protected with some lens coating and should have multiple layers on all air-to-glass surfaces.

The highest lens coating level is known as fully multi-coated lenses.

Ocular Lens

The lens which is located closest to the shooter’s eye when seeing through the riflescope tube is the Ocular lens.

The eyepiece contained the Ocular lens. It is used to focus the image created by the Objective Lens by adjusting the Eyepiece.

Like the Objective Lenses, the diameter of the Ocular Lens is also measured in millimeters. The ocular lens has a direct effect on the field of view of the scope.

The larger the Ocular Lens is, the larger the field of view of the rifle scope will be.

Main Tube of the Scope

The main tube is constructed from metal that contains both the Ocular and Objective lenses. It is also called the body of the riflescope.

It can vary in diameters of 25 mm, 30mm, and 34 mm, this largely depends upon the brand and the type of the scope.

A scope with larger tubes allows for more space for internal components and increases the range of adjustment, which does a better job for long-distance targeting.

The majority of the rifle scopes available on today’s market come with the main tube having a 1-inch diameter.

Generally, The scopes with larger tubes are more robust than the 1-inch scopes.  Contrary to popular belief, the larger tube does not mean more light.

The exit pupil controls this. However, the larger diameter gives you added strength and rigidity.

But the larger diameter scope has more weight and every extra ounce can weigh you down during your hunting.

If you are looking to minimize the weight then 30mm may be something to consider.

Exit Pupil

It is a virtual aperture within the scope tube through which all light entering the Objective Lens must pass through the ocular lens.

Only light rays which pass through the exit pupil can exit the system. It is measured in millimeters.

One of the main factors which play a significant role in the low-light performance of a riflescope is the exit pupil.

The larger the diameter of the objective Lens is, the larger diameter of the Exit Pupil will be and the brighter the image will be in any light condition.

To determine the size of the exit pupil, you can divide the objective Lens diameter with magnification power.

For example, a scope having the diameter of the objective lens of 28mm and magnification power of 4x will have an exit pupil of 28/4 = 7mm. A 4mm exit pupil throughout the magnification range is recommended for a hunting scope.   

Field of View

This is the amount of view measured horizontally that you see at a distance of 100 yards when you look through your riflescope.

It is measured in feet at 100 yards. A higher number indicates a wider area and it is desirable in a rifle scope.

As a general rule of thumb, As magnification is increased, the Field of view goes down and when magnification decreased, the field of view increases.

For quick target acquisition in close cover, a scope with a wider field of view and a smaller power is recommended.

Lens Coatings

In this Riflescope Buying Guide, we are going to tell you another important thing to consider and that is Lens Coatings.

The special coatings on the lenses reduce the glare and the amount of lost light due to reflection.

The light which strikes a glass lens at an angle of fewer than 48.5 degrees is reflected and it does not pass through the Objective Lens.

However, a thin chemical film coating is used to reduce the reflection. These coatings reduce light loss and glare and give you better light transmission and brighter, clearer images.

The four different terms used for coatings are:

  • Coated: A single layer on at least one surface of a lens.
  • Fully Coated: A single layer on all lens surfaces.
  • Multicoated: Multiple layers on at least one surface of a lens.
  • Fully Multi-Coated: Multiple layers on all air-to-glass lens surfaces.

Some scopes have coatings that protect from scratches while others have coatings that prevent water from staying on the glass.

The Hydrophilic and Hydrophobic coatings allow clearer views in rainy or misty conditions.


A reticle is a pattern of lines built into the eyepiece of a scope which provides you with an aiming point.

These visual markers are also known as crosshairs. Reticles come in several different types and each one is appropriate for a particular shooting situation.

Some of the most common reticle designs are mentioned below.

  • Crosshair reticle: It was the first reticle designed for the riflescope. It is still one of the most popular reticles. One Horizontal and one vertical line cross each other in the center and give you an aiming point.This is best for any precise shooting but is not always ideal for hunting.
  • Duplex reticle: One of the most common reticles on the market is the Duplex reticle. Many hunters and shooters around the globe consider this the best reticle.All four thick lines starting from the circumference thin out to the center of the circle.The combination of thick to thin lines allows you to quickly aim at a moving target.

    Most scope manufacturers have their own name for this reticle.

  • BDC reticle: The BDC or Bullet Drop Compensation reticle is a modified form of a Duplex reticle. It is designed to compensate for the effect of gravity on bullet drop. This reticle has some type of markings at the 6 o’clock position.These extra marks allow you to accurately shot the bullet. The BDC reticles are best for long-range shooting.
  • Mil-Dot Reticle: It uses milliradian dots on all four lines for measurement. Each 1 Mrad on the reticle is equal to 3.6 inches at 100 yards and 36 inches at 1000 yards.Using a mil-dot scope is a very complex operation, therefore, this reticle is not recommended for beginners.This reticle is ideal for snipers and extremely long-distance target shooters.
  • Illuminated/Non-Illuminated Reticles: A reticle having some light which allows you to hunt in low light conditions. It comes in a variety of different combinations and colors. All types of reticles can be illuminatedso that you can easily see the crosshairs such as BDC illuminated reticles and Duplex Illuminated Reticle.While the simple black color reticle having no light is called a Non-Illuminated reticle.

Focal Plane

Another important thing to consider in this Riflescope Buying Guide is its Focal Plane.

There are two types of focal planes, the first focal plane (FFP) and the second focal plane(SFP).

All the riflescopes with variable Magnification power have reticles positioned in either the first focal plane or the second focal plane.

The reticle located in the first focal plane (FFP) means the reticle increases or decreases with the target when the power setting is changed.

The First focal plane is also called the front focal plane.

The Second Focal Plane(SFP) or rear focal plane is the simplest and most common reticle placement style.

The reticle in the Second Focal Plane remains the same size through the entire magnification range and it does not change with the target.

The Second focal plane scopes are smaller and lighter and most of the hunters in America prefer second focal plane rifle scopes.  

Eye Relief

It is the distance from the last surface of an eyepiece to your eye that allows the shooter to see the entire image comfortably.

Eye relief is important for some reasons. First of all, the heavy recoiling rifles can make quite an impact on the shooter’s eye socket and can put the eye in danger if the eye relief is too short.

Secondly, people who wear eyeglasses need longer eye relief to see the full range of the image in the scope.

So it is very important to choose a rifle scope with appropriate eye relief. The 3 inches to 4 inches is a good number that will fit most hunters.

Parallax Adjustment

Parallax is an optical condition in which the image of the target is not focused precisely on the Reticle Plane.

It is an inconsistency in the view when you look through the rifle scope. The reticle will not accurately reflect where you aim your rifle.

It is usually an issue at magnification power over 10x. The standard focusing knob adjusts the reticle to your eye.

The scopes with a parallax adjustment give you a more clear sight picture. Most rifle scopes without adjustable objective lenses are factory set to compensate for parallax.

An adjustable objective will be a good choice when you are selecting the scope for long-range targets.

Eye Piece

The eyepiece is located on the end of the scope which is close to your eye when you see through the riflescope.

It consists of the Ocular Lens and the eye bell. The eye bell is a flared part of the rifle scope and contains the Ocular Lens.

The eyepiece is adjusted to focus the image created by the Objective Lens.


The external and raised knobs on the top and right side of the riflescope are called Turrets.

These target turrets are located at the beginning of the eye bell. These turrets serve the purpose of enabling the shooter to adjust the windage and elevation.

The objective of turrets is to adjust the bullet impact on the target by using the reticle crosshairs to raise, lower, or move sideways.

Each “clicks” on the turret equals ¼ of adjustment left/right or up/down at 100 yards.

It is called a 1/4 Minute of Angle (M.O.A.) and one Minute of Angle equals one inch at 100 yards.

These turrets are very easy and simple to use and can work with any magnification.

They give you more precise and finer accuracy. The scopes having turrets are more expensive than conventional rifle scopes.

Waterproof and Fogproof

A process of Gas purging prevents internal fogging of the lenses and makes the riflescope waterproof and fog proof.

In this process, all of the air from a scope tube is evacuated and it is then filled with a gas or a mixture of gas.

The most common are nitrogen or an Argon/Krypton gas mixture (both of which are inert).

The scope tube is then sealed to maintain the internal pressure so that moist air cannot enter the tube to fog the lenses.

Windage and Elevation

Modern scopes adjust for point-of-impact by using two knobs, one on the side of the scope and the other on the top of the rifle scope.

The knob on the side is for windage adjustment and Windage is the term for horizontal adjustment of the scope.

The knob on the top is for elevation adjustment and elevation is the term for vertical adjustment.

Types of Scopes[Riflescope Buying Guide 2023]

There are plenty of different rifles available on the market and scope manufacturers are producing specially designed riflescopes for each type of rifle.

Some of the most common and best-selling rifle scopes are listed below.

308 scopes

The .308 Winchester is a rimless and bottlenecked rifle cartridge that is the most popular round in the United States and probably around the globe.

It is commonly used for civilian hunting, target shooting, military use, and police sharpshooting. The .308 is the best choice for long-range precision shooting.

All sorts of 308 caliber rifles are built for it, ranging from entry-level hunting bolt action rifles to precision match-grade semi-autos.

Different riflescope manufacturing companies have built specially designed scopes for 308 caliber rifles.

The 308 rifles along with specially designed scopes give you incredible accuracy for long-range shooting or hunting.

Some of the top-rated and most-selling 308 scopes of this Riflescope Buying Guide are Nikon M-308, Leupold 115370 Mark AR, and Vortex Optics Crossfire II 2-7×32.

17 HMR Scopes

.17 Hornady Magnum Rimfire(.17 HMR) is a rimfire rifle cartridge. It was developed by   Hornady, an American ammunition company in 2002.

The 17HMR is now becoming popular for hunting, target shooting, and plinking. It has a flat trajectory up to 100 yards. The .17 HMR cartridge is extremely powerful at close range.

The .17 HMR caliber rifles are popular for their flat and accurate shooting abilities. Adding a scope to the rifle improves its accuracy even more.

These 17 HMR rifles deserve the fine scopes to get the maximum benefit from the round. There are many scopes for 17 HMR rifles available on the market.

Some of the best-selling 17 HMR scopes are Leupold 110827 VX-2 Rimfire Riflescope, Vortex Crossfire 2-7x32mm, and BSA 6-18X40 Sweet 17 RifleScope.

AR 15 Scopes

The AR-15 rifle is a semi-automatic and lightweight rifle based on the Colt AR-15 or M16 design.

In 1956, ArmaLite an American arms engineering company designed and developed a lightweight assault rifle for military use and named it the Armalite Rifle-15, or AR-15.

Today, So many manufacturers are producing their own version of the AR-15 design. The AR-15 rifles are the most beloved and most vilified rifles in the United States.

There are many benefits of using the AR15 rifles and some of them are listed below.

First of all, It is one of the most ergonomic semi-automatic rifles around the globe and is comfortable to shoot.

Secondly, the recoil of this AR15 rifle is limited and manageable and this makes it an easy-to-shoot rifle for anybody.

Finally,  it is the most popular rifle sold in the United States today. Its aftermarket parts and accessories are available in abundance on the market.

You can use this rifle for everything from casual target shooting to home defense to hunting wild hogs, pronghorns, and deer.

From a beginner to a seasoned pro, adding a scope to your  AR 15 rifle will drastically improve your performance.

The AR 15 scopes are specially designed to deliver precise shots on target. All leading brands such as Nikon, Leupold, BSA Optics, and more are manufacturers of AR15 Scopes.

Some of the best AR15 scopes available on the market that we included in this Riflescope Buying Guide are Nikon Buckmaster II, 3-9×40 scope, Leupold VX-R Patrol, and UTG 3-9×32 scope.

AR 10 Scopes

The ArmaLite AR-10 is a 7.62×51mm NATO battle rifle developed by Eugene Stoner in the late 1950s and manufactured by ArmaLite, then a division of the Fairchild Aircraft Corporation.

When first introduced in 1956, the AR-10 used an innovative straight-line barrel/stock design with phenolic composite and forged alloy parts resulting in a small arm significantly easier to control in automatic fire and over 1 lb (0.45 kg) lighter than other infantry rifles of the day.

Over its production life, the original AR-10 was built in relatively small numbers, with fewer than 9,900 rifles assembled. However, the Armalite AR-10 would become the progenitor for a wide range of firearms. (Wiki)

The AR10 is a lightweight, air-cooled, and gas-operated rifle having 20 round detachable box magazine.

It weighs between 3.29 to 4.05 kilograms without ammunition and a magazine. The addition of a quality scope that works for your AR rifle to meet your end goal is a must-have.

There are so many options for AR-10 scopes these days by top brands. Some of them are Vortex Optics Diamondback 4-12x40mm, Leupold VX-2 4-12x40mm scope, and Nikon ProStaff 4-12×40.

Thermal Scopes

Thermal imaging is a method that allows you to see people or objects that cannot otherwise be seen by the naked eye.

Every object emits heat in the form of infrared energy as a function of its temperature. The hotter objects emit more radiation and this emitted infrared energy is known as a heat signature.

A thermal imager detects the tiny differences in temperature and they appear as distinct in a thermal image.

Thermal scopes are the coolest optical devices that you can install on your weapon.

They offer you the flexibility of daytime, nighttime, and in any weather condition use when other scopes simply fail.

Thermal scope clears the vision and directs you to your target. Thermal scopes can be used for various applications.

Some of the best thermal scopes that are worth the money you are spending on it are ATN Thor HD 384, Pulsar Core RXQ30V, and IR Defense IR Hunter Mark II 640.

Hope this Riflescope Buying Guide will help you in finding the best optic for your firearms.

Read: How to sight in a scope? 

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