Midway Shooting Supplies

Magnification

Magnification is the reason we buy a scope, to begin with, but it isn’t as simple as picking the biggest number.  There are a variety of reasons why someone may choose a scope of a greater or less power. Don’t get carried away with magnification, let this short section provide some guidelines on what you really need.

The primary effect of magnification is to make a target appear closer than what it is.  A 2x magnification rifle scope will make a target appear half the distance away. 10x would make it only 1/10 the distance. This logic would tell you that more magnification is better but this is hardly the only effect.

The first negative of greater magnification is price.  Typically a more power rifle scope will cost more than the same scope with less magnification.  There are other factors that affect price but this is the most prominent.

Acquiring a target will be slower the more magnification you have.  This is mostly due to a decreased field of view but can also result from simply moving the scope so fast that it passes the target before you notice it.  This is especially true of smaller targets.

Without very good lenses with multi-coatings, a more powerful rifle scope will appear darker.  It takes more light through lenses to make a target appear bright. As magnification goes up, so does the amount of light it takes.  Cheap, powerful scopes can appear very dark to the point of being almost unusable.

All of that said, a more powerful rifle scope has the potential to improve your chances of hitting distant targets.  It will take practice to get the skills needed down but you will never be able to hit something you can’t see well.

Fixed and Variable Power

With a basic understanding of magnification, we can look at a normal scope, let’s say 10×44, and know that it is a 10 power scope and objects will appear 10 times closer.  More commonly though we will see a rifle scope that is 4-12×50. This is a variable power scope.

Variable power scopes are capable of magnifying a target anywhere in a range of powers.  The example above would be anywhere from 4x magnification to 12x. This is done by a dial at the eyepiece that extends the distance between the focal lens at the eye and the prism at the erector.

These are very popular because they offer a better blend between fast target acquisition at closer ranges and great power for long distance shots.  While most of these scopes are very good, there are a few points to be aware of before you decide these are right for you.

Because a variable power scope has more moving parts, it will be somewhat more expensive with more potential points of failure.  As price increases, chances of failure decline but it will never be less prone to failure than a fixed power scope.

If you use a rifle scope with a bullet drop compensating reticle, picking a variable power scope will require you to make a sacrifice.  This will be covered more in the section on Focal Planes but suffice to say that you can’t have everything. There are negatives both ways.

Even with those few negatives, these are usually the best bet when buying a scope.  They are far more versatile than a fixed power and can be specifically tailored to each shot.  For hunters, this is even more important than with target shooters.

Focal Plane

Focal plane specifically deals with reticles and how they are displayed on a variable power rifle scope.  The exact physics of how this happens is unimportant but it is very important to understand the effects this could have on how you use your scope.

To understand the effects of what you see, on a first focal plane scope the reticle will change size as you zoom out.  At maximum zoom, it will be quite small where on minimum zoom it will fill most of your view. This can make it hard to see markings on the reticle when you are at max power.

On a second focal plane scope, the reticle will always appear the same size.  This means that the distance between any marking on the scope will change as you increase or decrease magnification.  This will affect bullet drop compensation and ranging tasks.

On a second focal plane scope, the reticle is calibrated to work at a specific magnification, usually the maximum.  If you have a ranging reticle, it will only be accurate at the range the reticle is calibrated to. There are methods of doing the math to be able to range at different magnifications but it is somewhat complex, slows down shots, and you have to be very precise on what exact magnification you are using.

On a first focal plane scope, you will have none of those issues.  The scope’s reticle will preserve the aspect of the reticle at any range.  It can still be difficult to range at longer distances because of the smaller reticle but it will give you more accurate measurements overall.

Occasionally if you get a cheaper variable power rifle scope, you may have issues where there is some reticle shift as you change magnification.  This is a serious issue that will cause your scope to only be accurate at the magnification you used to zero the scope.

Objective Lens Size

The objective lens is the one opposite the eyepiece where light enters the scope.  This light is what transfers the image to your eye and an improperly sized objective lens will make the overall image of the scope appear dull or dark.

Having a larger objective lens will improve the ability of your scope to perform in lower light conditions.  This is an important trait for all scopes but absolutely critical to the hunter who often hunts at dawn or dust.  Without an appropriately sized objective lens, the chances of being able to distinguish between your target and the surrounding terrain will be greatly diminished.

While there are formulas to determine the appropriately sized objective lens on a rifle scope, that is usually unnecessary.  Most scope manufacturers have a system to ensure the objective lens is sized correctly. When looking at a scope, compare the size of the objective lens to scopes of a similar maximum power.  If it is noticeably smaller than other scopes, there may be an issue.

While it is less common, having too large an objective lens can cause problems as well.  Excessively large objective lenses are commonly used by cheap scope manufacturers to make their scopes perform with lower quality parts.  Mounting a large diameter scope like this will require special hi-rise rings. Mounting your scope so high can cause issues with accuracy.

It is important to note that the objective lens is not the only factor that contributes to brightness in a scope.  Lens quality and lens coating will also have an effect on the amount of light transferred. However, this does little to correct an improperly sized objective lens.

Lens Quality

This is a tricky one to cover but lens quality on a rifle scope is one of the most important factors in its overall quality.  No matter what a company does, bad glass will always be bad glass. You can’t do anything that will make it better.

Poor quality glass may appear dark, smoky, or dull.  It may mute colors or even cause the whole image to blur into an indistinguishable mess at as range increase.  If you have ended up with a scope that does this, there is little you can do to help it. You are better off replacing it and moving on with a quality product.

The trickiest thing about lenses is that nobody announces that their glass isn’t up to par.  The only way to distinguish glass quality without looking through the scope is to go by brand reputation and the word of others who own the scope.  This is a more subjective way of determining the quality of a scope but you take what you can get.

There are a few keywords you can look for on the higher end of scopes that will give you some indication of lens quality.  You may see terms like ‘ED Glass’ or ‘ED Prime.’ If a scope uses glass that is extra-low dispersion like the previous two examples, it is usually very good quality.

Lens Coating

One of the primary ways of improving glass quality has always been by using lens coatings.  Predominantly these work to reduce glare and filter the light spectrum to improve the overall image through a scope.  While this used to be a staple of only the best brands, many budget optics companies and even some cheap companies have found the value of lens coatings.

There are 4 classes of lens coating classes that you may see on an optic:  Coated; Fully Coated; Multi-Coated; and Fully Multi-Coated. These go up in increasing quality but also cost.  Without exception, you are far better off spending a little more on a rifle scope to get good lens coatings.

So, what are these coating levels?

• Coated lenses have a single chemical applied to the objective lens.  Most commonly this is just to prevent glare and is common on most modern rifle scopes even if it is not mentioned.  Having a scope without at least a coated objective lens will make shooting in bright light more difficult.
• Fully coated lenses have a single chemical applied to every lens.  Again, this is usually a coating to reduce glare and is frequently used without the manufacturer specifying it.  This has become a somewhat standard practice for budget scopes that do not opt for higher quality treatments.
• Multi-coated lenses have either layers or a mixture of chemicals applied to a single lens.  This can be the objective lens or eyepiece. Usually, this multi-coat will filter the light spectrum for better performance while also reducing glare.
• Fully multi-coated lenses use the same mixture or layers on each air-to-glass lens surface.  This is the premium level of coating and should be the staple of a decent rifle scope.  While some budget companies to use inferior multi-coat just to say they have it, those are very rare.

While that covers the majority of coatings there are two other types that you may see that have no direct effect on lens quality.  Many scope companies have recently begun applying a lens coating to prevent stretching and damage. As scope quality has increased, the lenses have always been a weak point.  Having a coating that protects them is invaluable.

A second type of special coating reduced fogging of the lenses.  Though most optics have other ways of dealing with this problem, some more affordable scopes will use this as a cheaper method of fog control.

It should be noted that just because it has this treatment doesn’t mean it is cheap.  Some reputable brands will use this as a safety margin to ensure their scopes don’t have any fogging issues.

Reticle Pattern

No part of understanding an optic is more troublesome than that of reticles.  There are dozens of styles that differ greatly in their complexity and use. Getting the appropriate reticle for your needs, skill, and comfort level is probably the hardest but most important factor in selecting a scope after magnification.

Luckily, reticles can be divided into 3 categories.  If you can settle on which category of shooter you are, picking a reticle is a very simple task.  If you need more help, this reticle guide goes into detail.  It also covers the focal plane for added value!

Crosshair & Duplex

The most basic reticles are crosshair reticles that are simple crossed lines, the same that has been used by rifle scopes since they were invented.  A step beyond that are duplex reticles which are the same crosshair but with a change in line thickness near the center.

Both of these reticles are perfect for hunters whose primary goal is to increase accuracy without increasing range.  Many varmint and deer hunters use scopes like this. There are even models made for shotguns.

The duplex style has the added benefit of giving you a little bit of capability to determine hold-over more accurately.  This takes practice and familiarity with the scope but it can be useful. A secondary benefit is of the duplex reticle is visibility.  It is easier to see the thicker lines in poor lighting and they will lead you to the cross in the center.

BDC & Ranging Reticles

The most complex reticle styles are those made to help in determining bullet drop over distance and to aid in determining range to a target.  It will take a little practice to learn to properly use the bullet drop feature and even more to get the hang of using a reticle to determine distance.

While both of these are great skills to have, if you never intend to use a rifle scope for longer range, the added cost and complexity of these reticles is probably not worthwhile.  You may be better served by getting a simpler reticle style.

The two standard measurements for BDC reticles are MOA (Minute of Angle) or Mil.  Both of these are just ways of measuring the measurements of something mathematically when the distance is known.  Conversely, you can use these to determine distance when the measurement of something is unknown.

In addition to these two standard measurement types, many companies have developed their own proprietary reticles based on these standards.  These can be more or less complex, depending on the company but are more likely to be about the same.

While there is a lot to understand about these reticles it would take an article all its own.  Or take the easy route and check out this video.

Shaped Reticles

The final reticle class are those that are shaped.  These could be circles, dots, chevrons, or a combination of those.  While these are usually a very simple reticle to use, they can have a lot of complexity built in such as bullet drop.

This type of reticle is very fast, usually faster than using iron sights on a tactical rifle.  However, it is only a viable choice on rifle scopes of relatively low power. Usually, anything more than 4x or 6x has too much magnification for this type of reticle to be accurate.

While they share many traits with red-dot sights, they are not the same thing.  Usually, a red-dot has no magnification or very little. The lines may blur somewhat but this is a traditional rifle scope that has a reticle with a pattern other than crosshairs.

*A special note considering reticles.  Some optics are intended for use with a specific caliber of rifle.  Pay attention to this fact. If you use the wrong caliber with a caliber-specific reticle, it will not function correctly.

Adjustments

When we talk about adjustments, we are mostly referring to how we adjust for windage and elevation (Left/Right and up/down).  However, we are going to lump in focus as well to be complete.

For the first, windage and elevation, there are two types of adjustment.  Capped adjustments are screws that adjust with a coin or screwdriver to move the center of the reticle.  This is the oldest and simplest method of adjustment and is found on most hunting scopes. Once you are zeroed, you put the caps back on and leave it be until you need to re-zero your rifle.

Turret adjustments are more complex.  They allow you to adjust your zero to current conditions.  While you will set up your initial zero to get the rifle scope on target, afterward you are still able to adjust based on distance and environmental factors.

The best and most useful of these scopes have a zero-reset ability that allows you to loosen the turret and move it without shifting the point of aim of the scope.  You can then line up the zero with a marker on the scope housing. This gives you a good starting point when making range and wind adjustments.

All scopes have focus but there are two types of focus to be aware of.  The first is the standard focus used on all optical devices. All this allows for is to get both the reticle and target both into focus at the same time.  The actual premise of this is the same as with parallax focus but much less complicated.

For shots under 200 yards or so, you will never need parallax focus but for longer shots, you do want your scope to have this feature.  To reduce it to the very essence, parallax occurs when your target and reticle are not on the same focal plane in the scope. This will cause missed shots at longer ranges.  You can tell if your parallax is out of focus if your crosshair tends to move around the target as you move your eye.

This is a complex phenomenon that could take hundreds of words to explain.  To get a more complete understanding, Winchester Ammunition has this very good and concise article.

Eye Relief

Eye relief is simply the distance your eye can be from the eyepiece of your scope and still get a full, clear picture.  If you see black around the edges of your scope, your eye is too far away. Be aware that this is the maximum distance as your eye can be closer without issue on most rifle scopes.

While having a little extra eye relief is usually a good thing, sometimes your weapon may not be set up in a way that you can move your eye back far enough to take advantage of it.  In which case you are just wasting money on a feature you can’t use.

The main reason you may want more eye relief is when you are using a more powerful rifle, extra eye relief will prevent the scope from hitting your eye when the rifle recoils.  If you have never had this happen, you never want to. If you are lucky, you just get a black eye and a small cut. If you are unlucky, it could be a trip to the hospital with broken facial bones or even a damaged eye.

If you are shooting any magnum caliber rifle, you will want some added eye relief.  Any rifle that is reputed to have a hard kick will require a little extra. You know better than anyone how you handle hard recoils and how steady you can keep a rifle.  If you know you are going to have issues handling the recoil, go with a scope with more than 3.5 inches of eye relief.

Field of View

The field of view of your scope is simply the distance from one side of your view to the other at a specific distance and magnification.  To make it simpler, if you are using a 10x scope with a field of view of 35 feet at 100 yards when you are looking at that distance you will have a total of 35 feet from the farthest left you can see through the scope to the farthest right you can see.

Why is field of view important?  There are two schools of thought on the matter and both are valid.  Which is most important to you will depend on how you plan to use your rifle scope and your own mentality and focus.

Scopes with a very wide field of view will allow you to get on target faster as well as locating targets easier.  The more you see the easier it is to find a target, keep it in your sights, and recover after your shot to be back on your target.  However, if you are shooting small targets or for high precision, having the extra space around your target can cause distractions.

Scopes with narrow fields of view eliminate the distractions around your target to help you fully focus.  But they will not give or allow you to easily find your target through the scope and moving targets will be very tough to follow.  You will also be blind to anything going on around your target that could represent a safety risk.

A good rule of thumb is to reserve the narrow field of view scopes to the range and use the wider FOV scopes for hunting and tactical situations.

Illumination

While the vast majority of rifle scopes have no electronics and no need for them, the popularity of having scopes with illuminated reticles has surged over the past decade.  There is ample reason for this with the growth and popularity of defensive shooting competitions and the use of optics for home defense.

Generally illuminated scopes are low to moderate power as higher powered scopes encounter issues with the light inside the scope washing out its surroundings.  Usually 8x to 10x is as high as you will find illumination and that can be pushing the limits of the technology.

Some rifle scopes have fully illuminated reticles.  Typically, these are somewhat problematic because of the excess light required to provide that much light.  It is far more common to see just the center of the crosshair illuminated.

Those rifle scopes with shaped reticles will more commonly feature illumination and will generally illuminate the entire shape of the reticle.  Since these are lower powered optics, they tend to work fairly well.

If you are going to be hunting the rare animals that it is legal to hunt after dark (coyote and hog, check your state laws), you may want an illuminated reticle.  If you hunt deep woods for deer or other game, you may have reason to consider an illuminated scope. If you are using a lower powered scope for home defense or tactical situations, illumination can be a good thing to have.

Otherwise, go without it.  In your day to day shooting and hunting needs, it will never be an issue.

Durability & Weatherproofing

Scopes are an investment and the best scopes will often cost more than your rifle does.  Because they are usually made of aluminum and glass, they do take some care and caution to keep working.  Even the toughest scopes can break if treated badly.

To help with this, there are a variety of different features built into a scope to keep it working as it should.  The most apparent of these is to use a thicker aluminum and make the scope out of a single piece without joints or welds.  This goes a long way in keeping the internals safe while also keeping the lenses and prism properly aligned.

Many scopes today are optic for sealed interiors that keep out moisture, dust, and debris.  The internals of a scope are very sensitive and foreign matter can wreak havoc. A step above this are those companies that purge the internals of air and replace it with an inert gas like nitrogen or argon.  This further prevents moisture from getting in as it does not expand or contract with temperature changes.

Above the lens coatings that prevent scratches was mentioned.  Scope companies may also use a hard coat anodizing process to prevent damage to the outside of the scope body.  While this is usually just cosmetic damage, scopes are expensive and should look good.

The final line on durability is the warranty.  Whenever possible get an optic with the best warranty possible.  Some things are out of your control and accidents happen. If you are going to invest in a great scope, make sure it has a great warranty to back it up.

Always check to make sure your rifle scope is compatible with your rifle.  Many scopes advertise themselves as shockproof but they give no indication of how shockproof.  A hard enough recoil can break many scopes that should be tough. For anything under .308, you are fine with most any scope.  If you go for a large magnum, do your research or contact the manufacturer.

Types of Scopes

While it is possible to use a rifle scope for multiple purposes, you are likely to be more satisfied if you purchase one based on your primary need for the rifle you are putting it on.  You can use it for other uses after but your main use should be the one that dictates the scope you buy.

While most scopes are not clear cut, to begin with, here are a few criteria that will get you in the ballpark as to what would be the best use for the scope you are considering.