THE DIRT ON RIFLE SCOPES

Rifle scopes are one of those pieces of equipment that seem to be shrouded in mystery for most people. To make matter worse, many salespeople at many of the bigger box stores are teenagers, looking to make a few bucks over summer and have no real passion for target shooting, hunting or any other discipline involving firearms. This leads to too many shooters, especially beginners, buying equipment they don’t need, don’t understand and can’t trouble shoot.

This article is written for preppers but will apply to hunters, long range shooters and anyone who uses rifles for any reason. If you own a rifle, chances are you have or will one day use a scope. This article will hopefully shed some light on the great mystery that scopes seem to be.

In the world of disaster preparedness or an economic collapse, firearms will play a major role especially in the role of food procurement. A good rifle will keep a family fed for a long time, and anyone who takes self-reliance seriously should consider taking up hunting for that reason. Unfortunately, acquiring clean, healthy meat means that one hast have all his “ducks-in-a-row”. A small but important part of this formula is the rifle scope.

Some rifles still come with iron sights which are simple to use and almost unbreakable but most rifles do not. All rifles today will have the option of mounting a scope on the receiver and as complicated as it might seem to a new shooter, remember that when you have to eat, the scope will make it a lot easier to take the game. This is because you can take it from much further away than iron sights. When you’ve been starving for two weeks, you will want to make it as easy on yourself as possible…

THE BASICS

First, let’s go over the parts of a rifle scope and what they do.

The above picture illustrates the basic parts of a scope. Moving from top left to bottom right, let’s talk about how each part functions. All scopes will have most of these parts and therefore what you learn here is applicable to most scopes. Exceptions will be discussed as well.

THE OBJECTIVE LENS

The objective lens of the scope is usually, but not always, the largest and it is closest to the muzzle of the rifle. The objective lens is measured in millimeters and the larger the lens, the more light will be transmitted into the scope. This will provide clearer sight picture but that is only half the formula.

The second part of the formula is glass clarity. What makes a good scope good, is the quality of the lenses. Or the lens manufacturing process. Glass is the same world over but how lenses are cut from particular glass, cleaned, polished and coated is what truly defines a scope. Some of the finest lenses on the planet today belong to the European manufacturers such as Meopta in Czech Republic, Zeiss and Schmidt and Bender from Germany, and Swarovski of Austria. These are some companies that have perfected the art of lens making and are essentially on top of the heap when it comes to lens quality.

The better the lens (glass) is, the clearer the picture will be. With 100% light transmission, your sight picture would be completely flawless and you would be able to see very fine details on targets once you increase the magnification. No one however, has thus far build a lens with 100% light transmission. There are scope manufacturers who claim mid to high nineties for light transmission but that is usually only the objective lens. As the light passes through the remaining lenses in the scope, more light reflects and less and less light makes it to the eye. A good scope might transmit 80% of all available light and mediocre scope significantly less.

SCOPE BODY (TUBE)

There are several scope tube sizes. The usual North American standard used to be one inch diameter (25.4 mm). Today more and more scopes are manufactured with 30mm and even with 34mm tubes. The larger tubes were designed for only one reason and that is higher range of adjustment on windage and elevation turrets. The further out your target is, the more you will have to adjust for bullet drop and therefore, the more room you need to adjust.

WINDAGE AND ELEVATION KNOBS

As the name implies, these turrets or knobs are used to change to point of impact of the bullet at a given distance. The elevation turret (top of the scope) dictates the impact of the bullet in an up and down fashion. The windage turret (right side of the scope from the shooters view) governs the movement of the impact of the bullet in left and right fashion.

These turrets are used for two functions. First they will help you sight the scope in. After the scope has been mounted and if the rifle sat in the gun locker for more than a month, the zero of the scope must be confirmed with live ammunition at the proper distance. The windage and elevation turrets are used to move the bullet impact in the needed direction to sight the rifle in.

The two turrets are also used to compensate for bullet drop and wind. As gravity acts on the bullet in flight, the shooter must predict the trajectory of the bullet and compensate by turning the elevation turret in the correct direction.

PARALLAX KNOB

Parallax induced error might be one of the most misunderstood aspects of shooting today. It is however, not complicated.

Imagine sitting in the passenger seat of a vehicle which is moving down the highway at one hundred kilometers per hour. As the driver sets the cruise control, the needle on the speedometer points directly at 100. Since you are sitting in the passenger seat you are looking at that needle from an angle and therefore, to you it seems as if the needle pointed at 96 kilometers per hour. This is a parallax induced error. How does this apply to scopes? Your line of sight may not go through the scope the same way every single time. If you place your rifle on a sandbag and look through the scope with the reticle placed perfectly on the target, then move your head slightly to one side, you will notice the reticle “moving” off the center of the target. The reticle hasn’t actually moved, nor has the target. Your point of view has changed. Just like it is your point of view that is giving you an incorrect reading on the speedometer of the car. If you didn’t understand this, you might want to compensate by moving the rifle “back into position” and as a result you would miss your target. Parallax knob will help you align your sight picture. Scopes without an adjustable parallax knob have the parallax set permanently at the factory. Centerfire scopes will have them set at 100 meters while rim fire, muzzleloader and shotgun scopes will be set at 50 meters.

MAGNIFICATION (POWER RING)

Magnification ring is the part of the scope which dictates how much you can enlarge your target. If it is a 3-9 scope, this means that the scope can magnify the target between three to nine times larger than if you looked at that same target with your naked eye. Not all scopes will have this feature as some scopes are fixed power.

OCULAR LENS/ADJUSTMENT

Ocular lens is the lens closet to the eye. All scopes will have an adjustment there as well. This adjustment is known as ocular adjustment or “quick focus”. This adjustment is needed to set the clarity of the reticle to the shooters eye. In order to accomplish this effectively, you must “isolate” your eyesight to the reticle only. In other words, you must select an object to look at that is neutral. Hold a blank piece of paper in front of the scope as you’re looking through it or look at the sky through the scope on a clear, sunny day. As you’re looking through the scope slowly adjust that quick focus until the reticle is razor sharp. When it is razor sharp, stop adjusting and do not touch the adjustment from here on in.

The reason you are looking at the paper or sky is because if you are looking at some target, your eye will naturally focus on that target and not the reticle. Your eye will also focus from one object to another and this will cause you to adjust the clarity incorrectly.

RETICLE

There are two basic types of reticles. Front (or first) focal plane reticle and rear (or second) focal plane reticles. The difference is that the front focal plane reticle will increase with the target as you increase the magnification. The second focal plane will remain the same size regardless of which magnification the scope is on.

From a simple “crosshairs” reticle, to complex bullet drop compensating systems, the basic function of this feature is to tell you where the bullet is going to end up. Think of it as a measuring tape that you are putting up against the target to measure how much you have to lift the barrel up to compensate for bullet drop.

TO TIE IT ALL IN

Let’s remember that all tools are built for a specific task. When you open you tool box at home, there isn’t one tool that will fix your furnace, help you change the oil on your car and help you with your gardening. It doesn’t exist. In the same manner, a Ferrari is designed to be race car. It is mean to be driven on paved surface, very fast with excellent cornering characteristics. One wouldn’t have very much luck with a Ferrari on a quad trail because it is not designed for that environment. In other words everything is purpose built. When you identify what purpose you will need a specific tool for, things get much easier.

For the ease of defining what is what, let’s assume that there are four different distance ranges. 0-200 meters is short range, medium range is 200-600 meters, long range is 600-1000 meters, and extreme long range is anything over 1000m. This is not a “set-in-stone” sort of rule but it will help us define what a particular scope is designed for.

Traditionally, about 95% of all big game hunting shots were taken within 200m. Today, as long range hunting and shooting is becoming more popular, that percentage is slowly shrinking but the vast majority of big game is still taken within 200m. For this distance the 3-9x40mm scope with parallax set at the factory at 100 meters, with one inch body has proven to be the most popular and ideal combination.

If you are a competitive shooter and consistently shoot at 1600 meters, you will find that a much more suitable scope will be one with 20 or 25 magnification, a 30mm main tube for higher range of adjustment when compensating for bullet drop, large 50mm objective lens with high quality glass to maximize light transmission especially at high magnification which narrows down your field of view which in turn hinders light transmission.

SHOOTING APPLICATIONRANGECALIBERSCOPE TYPE
Plinking10-75m22LR2-7×33, 3-9×40
Varmint Hunting74-400m.223 Rem, 22-250 Rem,4-12×40, 4-16×44,
Big Game Hunting SR50-200m308 Win, 30-06 Sprg,3-9×40, 2.5-10×40
Big Game Hunting MR200-600m7mm RM, 300 WM4-16×44, 4-18×44
Long Range Target1000m6.5 CM, 338 Lapua6-20×50, 6.5-25×50
    

The above table is a simplified view of how scopes might be applied to a specific purpose. Again, none of this is set in stone and there are instances where shooters have placed accurate shots at 600 meters with a simple 3-9×40 scope. This however is not the norm.

EMPTY PROMISES

There are many companies which promise the world when it comes to precision shooting. Endless videos on you tube show shooters take aim at animal, somewhere in the corner of the screen a number pops up indicating the distance of the shooter from the target in hundreds of yards, usually very close to the thousand mark. Then the shot is heard and the animal is seen tumbling down the side of the mountain as the camera pans out. Many people see this and think they can walk into a gun store, buy the gear and they can do what they “think” they saw.

Shooters who make these shots on regular basis however, have custom barrels, their rifles are benched out, high powers optics costing thousands of dollars but most importantly…trigger time. Practice reading the wind and understanding the ballistics of their calibers intimately. Understanding the effect of elevation, temperature, barometric pressure and many other factors. No one ever became a good shooter just by buying the gear and since some manufacturers would have us believe otherwise, there are lots more limping deer in the woods.

CONCLUSION

As mentioned previously, a good rifle will make life a lot easier in a disaster, or post collapse scenario because it will make feeding the family much easier. So what sort of combination might be the best? I would choose a 308 Winchester or 30-06 Springfield chambered, bolt action rifle with a 20 or 22 inch barrel. Scope would be a lower end Zeiss with about a 4-16 magnification with a 40 or 44 mm objective lens. I would practice shooting at targets from 100 meters to about 500 meters. If one cannot take a white tailed deer within those ranges, perhaps it’s time to get someone else do the hunting.

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