It is common for rifles and shotguns to look like something is missing when no hunting scope or other kind of sighting device is attached. They are becoming more and more popular for handguns, too. The main reason is that it makes it less difficult to hit your target, when it is further away, even though the firearms can have the iron sights built in. By looking into a magnifying scope or using a red dot laser sight, it is easier to see your target and get a more accurate shot.
All rifle scopes feature a sizing system called a number range, these numbers refer to a hunting scope’s magnification ranges and the diameter of its objective lens. The first numbers of a 3-9x 40 scope would mean it is a variable optic capable of 3 times closer than the naked eye and up to 9 times the naked eye in magnification. The important thing here is how low is the magnification, not how high. This is because as the magnification increases, the extent of light through the eyepiece is less.
The last number of the number range shows you the diameter of the objective lens, measured in mm. Generally, gun scopes use objective lenses with diameters of 40 to 45 millimeters. Some more extreme models range up to 75 millimeters, but this isn’t needed. The bigger the objective lens number, the larger it will be and the more light you will get through the scope. It is this fine balance of magnification and objective lens size than gives the best detail, this is essential for the most accurate shot.
Picking magnification size depends on how much magnification you will require. You should not forget that the lower the magnification, the greater the detail, but you also need to consider the size and distance of your targets. You want to select a 3-9x 40 hunting scope for hunting large targets like deer, but for smaller, more distant targets like pheasants or squirrels, you might need a 6-20x or an 8-25x variable rifle scope.
A scope’s objective lenses also can be variable or adjustable. External parallax adjustments can alter the diameter of variable objective hunting scopes. This can make a difference with hunting scopes with greater than 10x magnification. You won’t generally get this feature on optics with less magnifications.
Hunting scope lenses generally are water resistant and fog-proof. They are coated with one or more layers of coating to help lower loss of light and glare. Generally speaking, the more layers of this coating you have, the more defined the contrast and the better the object’s image will be. Hunting scope lenses which are fully multi-coated are always seen as the best because they usually give greater light transmission and give a sharper contrast.
Another phrase you will hear while you’re looking at hunting scope optics is Field Of View, or FOV. Field of View is refering to how many feet, left to right, you will be able see when looking through the scope. Normally your FOV at a 100 yard measurement using 3x magnification can be about 30 feet. As the magnification you use gets smaller, the Field of View goes up. At 9x magnification, the FOV is only about 14 feet.
You need to understand a rifle scopes dimensions when you are choosing the best overall scope for the kind of hunting you will be doing. As you now know, the measurements can make quite a difference in how precise your shots will be.
