What is Eye Relief on a Scope? – Scope Clearance Guide
Ever been out on the hunt and lost sight of your target because your lens suddenly lost focus or was blurry? Well, you’re certainly not the only one. The unfocused image in your optics can be due to a number of reasons, but a significant one is known as eye relief.
What is Eye Relief on a rifle scope? Eye relief is the distance between your eye and the ocular (rear) lens of your scope through which you can observe your surroundings. This range is important to ensure a clear, undisturbed image and to prevent your eye from straining too much.
It is usually measured in millimeters or inches. Typically, for rifle scopes, it’s best to measure the scope clearance in inches.
Eye relief is impacted by the magnification of your scope. The higher the magnification, the shorter the eye relief you have because of the shortened range. Your eye is closer by a half an inch or an inch to the eyepiece of the rifle scope. This basically means that if you use a higher-powered scope then you end up with shorter eye relief – the lower the power, the longer the eye relief.
Short Eye Relief
Scope clearance of fewer than 13 millimeters is referred to as short eye relief. The main struggle with short eye relief is that your field of view may be perfectly fine, but it’ll feel like you are pressing the scope lens into your eye to see through it.
For people who need glasses to see clearly need larger eye relief. Anything as short as or shorter than 16 millimeters can be problematic. Hence, for people who wear glasses, eye relief has to be longer.
Standard Eye Relief
The average length of standard eye relief is around 4 inches. Anywhere between those above mentioned 13 mm and up to around 4 inches of eye relief is what most hunters and shooters consider standard. Scopes that offer standard eye relief are ideal for rear mounting. They give you the leeway to have greater magnification and alter reticle positions.
These are features that the long eye relief scopes do not provide. You can get a decent amount of magnification and easily take aim at long-range shots.
Scopes with standard eye relief help maintain balance in your gun since the weight is more evenly distributed. Many scopes will give you clearance between 3.5 inches and 4 inches to make it possible that you mount the scope on the back with adequate eye relief to avoid scope bite.
Long Eye Relief
Many hunters do like scopes with long eye relief. Anything greater than 4.5 inches of eye relief is considered to be a long eye relief. A long eye relief scope offers extra room to people who wear eyeglasses and since your eye is not glued to your eyepiece, there is additional comfort in using it.
There is more room for movement with a long eye relief scope. Every tiny movement will not cause a disturbance in your image when adhering to proper eye relief.
Lastly, if you have a rifle with heavy recoil then using long eye relief scopes is usually your best option. Otherwise, you might end up with scope bite (see below) which you definitely want to avoid!
Some rifles and scopes come with extremely long eye relief. For example, a Scout scope will typically have a scope eye relief of somewhere around 12 to 16 inches, placing the optic towards the middle or even front of the barrel.
If you don’t follow the recommended eye relief settings of your rifle and scope, you may experience disturbances, such as chopped views or loss of light. The worst for most hunters and shooters is being in danger of the rifle scope hitting you during recoil.
Set the eyepiece based on your rifle and scope before you begin. Look through the lens and adjust the eyepiece as required to get the optimal picture. A high-powered scope additionally will have shorter eye relief when you’re at full zoom. Keep that in mind when looking for a scope as the higher-powered ones will often be a great choice for heavy-recoil calibers but on the other hand, end up closest to your eye!
Determining the Right Setting for Eye Relief
The specifications of your scope will determine where your scope should be mounted to have the correct inches of proper eye relief and provide you with a clear picture, the best light transmission, and the best possible field of view. The eye relief is the distance between your eye and the ocular eyepiece and it should be pretty clear where to position the scope on your rifle to get the correct clearance.
If you do not mount according to the specs then you won’t get great imagery when you use your scope. You shouldn’t expect a great scope image when you use a long eye relief scope and mount it on the back of your rifle. It’ll negatively impact the image quality as well as your field of view.
Impact of ignoring the recommended eye relief distance
Mounting the scope with the wrong eye relief range leads to a number of different problems with image clarity and seeing the entire picture overall:
- Reduced light transmission
- Reduction in the field of view
- Clipped images
- Scope bite when the scope hits your eye socket if mounted too close
Ideally, the exit lens of your scope should match the dilation of your pupil. The average diameter for the exit pupil is generally 5 millimeters.
In darker situations, the eye becomes more dilated for more light transmission. This can visually cause you to see a ring around the view from your scope lens.
Avoiding Scope Bite
Maintaining a balance between the distance from your scope and matching the diameter of the exit pupil, regardless of the amount of light available is the key to maintain the clarity of the image and optimize light transmission. Just make sure that the riflescope is mounted so you are not too close to the eyepiece to avoid being hit by the rifle’s recoil, whether it may be on your eye or the skin around it. If you use a rifle with heavy recoil then consider a scope with long eye relief to avoid “scope eye“.
If you position the rifle scope in the wrong position then you might end up getting too close to the lens in the hope to get a larger field of view. Being that close and not using enough eye relief distance is clearly a great recipe to catch some scope bite, also called scope eye!
To maintain good eye relief, some hunters and shooters opt for weapons with less recoil. That being said, other shooters may prefer to have a limited view and more recoil simply because they’re more comfortable with the rifle they’re using.
You’re in charge of making your own decisions but bear in mind that missing your target isn’t the end of the world! Potentially damaging or even losing an eye is a much more serious problem.
Regardless of how adventurous you are or how much you love feeding your thrill-seeking nature, avoiding harm to yourself is always a priority and avoiding scope eye is pretty easy!
Adjusting Eye Relief
Getting the right eye relief is the job of your rifle scope manufacturer. Certain calculations are required to get optimal eye relief measurements.
But every person is different, physically, and vision-wise. Generalized settings may not always be the right fit for you. Customize your riflescope settings to find the ideal shooting position that is most comfortable for you so you get a sufficient field of view, matching your exit pupil, and best light transmission when aiming.
It’s a relatively easy process and one that you should definitely follow to make your hunting experience an enjoyable one. Not only is your hunt more comfortable, having the right setting for your eye relief will also give you the opportunity to have a faster and better aim and an optimized field of view.
A 6-Step Process to Optimum Eye Relief
Step 1: When you’re attaching your scope to your rifle, make sure you keep the rings a little loose to allow for minor adjustments as required.
Step 2: Secure your rifle on a stable surface in a room/ place with sufficient lighting.
Step 3: Place the rifle on your shoulder and stand in your hunter’s position. Don’t think about looking through the scope. Your focus at this stage should be to find out the physical comfort level of the scope’s position.
Step 4: Look through your scope and adjust it till you have a very clear view.
Step 5: Continue this process till you’re happy with the position of the scope, both in terms of how it feels and the image quality you can observe.
Step 6: At this stage, you can tighten your scope rings.
Often, hunters don’t even know they don’t have the right eye relief settings. They may scrunch up their shoulders or twist their neck to get a clear field of view.
Even after you’ve adjusted the eye relief, make sure you adjust the windage and elevation adjustment turrets of your scope. Getting the right position requires both time and effort, but it’s well worth it when your body isn’t in distress and your aim is better than ever before.
Even if you’ve never considered it before, it’s time to focus on the eye relief of your scope. Rather than adjusting yourself to the scope, adjust the scope to YOUR needs.
Make it Your Personalized Setup
Just because you’ve spent a decent amount of time and money on picking out the perfect scope, don’t worry about damaging it with some small tweaks and adjustments. Set it up the way it works best for you within the parameters given by the rifle scope manufacturer.
If your ego and pride have been hurt countless times because your target was in sight and vanished within seconds because your field of view was limited, you might want to consider adjusting your rifle scope’s eye relief.
You may have spent a hefty sum on purchasing the best rifle, but it doesn’t stop there. You need to pair it with the right kind of scope set to the right adjustments which give you comfort and ease when you’re out on the hunt.
Most brands have scopes with different eye relief distances. Test a few to figure out which position works best for you and then get the best-rated rifle scope that matches your personal eye-relief settings. Rather than just screwing the scope into the rings straightaway, adjust the scope’s position for a clear and comfortable view before tightening the scope rings.
Gone are the days of missed targets and pulled shoulder muscles. Adjust the eye relief of your scope for a comfortable and enjoyable hunting experience.
You don’t need to look like a fool anymore, twisting and turning to get your scope to cooperate. Twist and turn the scope to get it to work on your terms and have a good hunt.