Understanding how to read rifle scope magnification is the first step to using your optic correctly. It tells you how much closer your target will appear, which is vital for accuracy at different distances.
This number is usually the first one listed in the scope’s model name or on the adjustment ring. Getting it right means you can match your gear to your shooting needs, whether you’re at the range or in the field.
How To Read Rifle Scope Magnification
Rifle scope magnification is shown as a set of numbers, like 3-9×40 or 4×32. The number before the “x” is the key. It tells you the level of magnification. The number after the “x” is the objective lens diameter in millimeters, which affects light gathering.
For a scope marked 4×32, the “4x” means it magnifies the image four times. A target 400 yards away will look like it’s only 100 yards away through the scope. It’s a fixed power scope, simple and reliable.
If the scope says 3-9×40, the “3-9x” means it’s a variable power scope. You can adjust the magnification from 3 times up to 9 times closer. You turn the magnification ring, usually at the eyepiece, to change this setting.
Breaking Down the Numbers: A Simple Example
Let’s use a common hunting scope, the 3-9×50, as an example:
- 3-9x: This is the zoom range. At 3x, you have a wide field of view for closer shots or moving targets. At 9x, you have a more magnified view for precise shots at longer distances.
- 50: This is the diameter of the front (objective) lens in millimeters. A larger lens generally allows more light to enter, giving a brighter image in low-light conditions like dawn or dusk.
Step-by-Step: How to Find and Set Your Magnification
- Locate the Magnification Ring. Find the ring on the scope closest to your eye (the ocular lens). It will have numbers printed on it.
- Read the Current Setting. Look at the marking line on the ring. It points to your current magnification. If it points between 4 and 5, you’re set at about 4.5x.
- Adjust as Needed. Turn the ring smoothly to change the power. Lower numbers for wider views, higher numbers for more zoom. Always keep both eyes open when possible to maintain situational awareness.
- Practice at the Range. Try shooting at different magnifications to see how it affects your sight picture and stability. Higher magnification can also amplify small shakes in your hold.
Choosing the Right Magnification for Your Task
Your intended use is the biggest factor in choosing magnification. Here’s a basic guide:
Close to Medium Range (0-300 yards)
- 1-4x or 1-6x: Excellent for fast target acquisition. Great for hunting in thick brush or for tactical use.
- 3-9x: The classic all-around hunting scope. Very versatile for most big game hunting situations.
Long Range Shooting (300+ yards)
- 4-16x or 5-25x: These higher magnifications help you see and aim at small targets far away. They are common for precision rifle shooting.
- Remember, higher power scopes are often heavier, have a narrower field of view, and require more stable shooting positions.
Common Mistakes to Avoid
When learning how to read rifle scope magnification, a few errors can trip you up.
- Confusing Magnification with Objective Size: Don’t mix up the zoom number with the lens size. They are two separate specifications that work together.
- Using Too Much Magnification: More zoom isn’t always better. At short ranges, too much power can make it hard to find the target in the scope. It can also make the image appear shakier.
- Ignoring the Field of View: The field of view is how much area you see left to right through the scope. Higher magnification means a smaller field of view. This is crucial for tracking moving game.
- Forgetting About Eye Relief: Eye relief is the distance your eye must be from the scope to see the full picture. It’s especially important on high-recoil rifles. Always check that your scope provides enough.
Understanding Related Terminology
To fully grasp your scope’s capabilities, know these terms:
- Exit Pupil: This is the small circle of light you see in the eyepiece. You calculate it by dividing the objective lens size by the magnification. A larger exit pupil (e.g., 5mm) gives a brighter image and is more forgiving of eye placement.
- Fixed vs. Variable: Fixed power scopes (like 4x) are simple and often very clear. Variable scopes (like 3-9x) offer flexibility for different scenarios.
- First vs. Second Focal Plane (FFP/SFP): This refers to where the reticle is inside the scope. In SFP (more common), the reticle size stays the same as you zoom. In FFP, the reticle grows with magnification, keeping subtensions accurate at all powers.
Practical Tips for Using Magnification
- Start Low, Zoom In: Begin with lower power to locate your target quickly, then increase magnification for the shot if needed.
- Consider Your Environment: In dense woods, use low power. In open fields, you can use higher power.
- Check Parallax: Many scopes with higher magnification (over 10x) have a parallax adjustment. This helps ensure the reticle doesn’t appear to move on the target if you shift your head. It’s usually a side knob marked with yardages.
- Match Your Reticle: Some complex reticles are designed for specific magnification ranges. Make sure you understand how yours works.
FAQ Section
What does the second number on a rifle scope mean?
The second number (like the 40 in 3-9×40) is the diameter of the objective lens in millimeters. It primarily influences how much light enters the scope, affecting image brightness.
Is higher rifle scope magnification always better?
No, not at all. Higher magnification reduces field of view, can magnify shake, and isn’t suitable for close-range shooting. Choose a magnification range that fits the distances you’ll most often be shooting at.
How do you adjust magnification on a rifle scope?
You turn the magnification ring, which is the ring at the rear (ocular) end of the scope with numbers on it. Rotate it to align your desired number with the reference mark on the scope tube.
What is a good magnification for a 300 yard shot?
A scope in the 3-9x, 4-12x, or 4-16x range is very effective for 300 yards. It provides enough zoom to see your target clearly while maintaining a managable field of view.
Can I use a high magnification scope for short range?
You can, but it’s not ideal. At very short ranges (under 50 yards), a high-power scope will have a very narrow field of view, making it difficult to aquire a fast-moving target. A lower power or variable scope set to low power is much better.
Knowing how to read rifle scope magnification empowers you to make better shots. It’s not just about the biggest number, but about the right tool for the situation. Take your scope out, practice adjusting it, and see how different settings change your view. With this knowledge, you’ll be able to confidently set up your equipment for success in any shooting enviroment.