Being a rifle shooter, you need to understand the technical aspects of the sport. It surely helps you a lot at various stages. For example, you will be in a better position to choose a specific weapon for yourself. Similarly, there is a huge variety of rifle scopes available these days on the market. It again requires basic knowledge about the technical aspects.
When it comes to the choice of a rifle scope, it simply comes down to the relation of rifle scope magnification vs. distance. Before you dig deeper into the matter, you first need to understand how to read the rifle scope magnification. You will find two numbers mentioned on the scope
- The first number is the magnification of the scope while
- The second number is the total diameter of the scope’s objective lens.
- For example, a specification 9×54 explains that the scope has a magnification of 9x and 54mm is the diameter of its objective lens.
Explaining the Rifle Scope Magnification
It would help if you understood that magnification of a rifle scope is its physical property, which means that it is about the
- Curvature
- Material of the lens
- Coatings
- Diameter
After you get to know these properties, you can easily calculate the optical qualities of your rifle scope with the help of a set of equations.
Functions of lenses inside a scope:
- Enlarge your target: you can have an enlarged view of your target as the objective lens catches the light reflected after it falls on the target, and then the light beam is directed to give you a magnified image of your target. You may find multiples lenses in some of the scopes.
- Flip the magnified view: Once the objective lens creates a magnified image, it is then inverted. As you might be familiar with the operation of a camera, the image is then inverted upside down. Now it is in the upright position.
- Focus your target image: Then, an ocular lens focuses the magnified image and flips it over for your eye to see. This is the ocular lens that defines the eye relief and the distance between your eye and the scope so that you can see a crystal-clear image.
The size and distance of enlarged image – The Equation
Now you need to understand the technical calculation to understand the relation of distance and the magnification of your scope. The ocular lens displays the image of your target, which just the reflection of the image instead of the actual image. So, you have to go further from here.
- The image and the target have a linear relationship which means they are directly proportional to each other.
- You can calculate the magnification as:
The focal length of Ocular Lens / Focal length of Objective lens
- Practically speaking, you get to know the extent to which your image differs from the actual target from the scope’s magnification.
- You can understand it like this: If you have a magnification of 4x, it means that the object will appear to be four times closer to you than the point it is located at. If your target is 100 yards away from you, it will appear to be 400 yards away through magnification in reality.
- The magnification and the apparent distance of the image have an inverse relationship. As you increase the magnification of your scope, the target will appear to be at an increased distance.
- The height of the target, on the other hand, increases with an increase in the magnification, which means that if you double the magnification, the target will appear to be at a half way distance. Still, the height of the target will appear to be doubled proportionally.
Physical limits of magnification lenses:
When you decide to buy high magnification lenses, you may have some limitations to face also. You need to have a detailed account of these issues to keep yourself right on your target.
Fringing: It is also known as Chromatic Aberration. It happens more as you opt for increased magnifications. This is a scientific phenomenon that occurs due to the variable wavelengths of different colors in light, just like a rainbow. So, if you view an object through a lens, it needs to be corrected for chromatic aberration to have a clear image instead of a blurry one with purple.
Spherical Aberration: Similarly, the spherical aberration may increase as you opt for higher magnification. This is another scientific phenomenon that happens due to the light hitting the lens surface on the edges and the center. Since the light strikes the surface of a lens at different focal points, you may have an image clear in the center but blurry on the sides.
The verdict:
Well! It would help if you always chose the rifle scope, which has perfect magnification as long as it enables you to hit the target. The high magnification does not guarantee that you will hit the target. It all comes down to testing the rifle scope and seeing the target, no matter what magnification the scope has. For the same reason, it is highly recommended that you try out taking a shot before you finally buy a specific scope.
However, long-range shooting, shots at small targets, and powerful rifles require high magnification scopes. So, it all largely depends on the circumstances and your personal preference
The trade-off between the distance and the magnification of your rifle scope reveals many technical aspects to you. Now you are in an ideal position to analyze what sort of scope you want for your rifle. There is no perfect measure of magnification of any scope. There is no standard, and it depends on several factors like the range of shooting.
The size of your target and, of course, the weight and power of your weapon. Therefore, the next time you go to buy the scope for your rifle, keep all these points in your mind when checking the scopes’ magnifications so that you get the best for yourself.
Oops? “If your target is 100 yards away from you in reality, it will appear to be at 400 yards away through magnification.” Got that backwards.
Thank you sir for your kind information.