What is Eye Relief on a Scope
Your hunting partner shows up to the lodge with an extended, deep cut above his right eye. His head is down so that no one would notice the badge of honor.
The mishap goes by many names:
- Scope Eye
- Bushweld Tattoo
- Weatherby Eye
- Magnum Eye
- Scope Bite
Rifle Scope
The distinctive cut is the result of a sharp blow to the brow bone, by way of a rifle scope recoil. Experienced and inexperienced shooters have endured the embarrassment of scope bite. Elite shooters know the importance of proper eye-relief and how to make sure it does not happen to them.
The shooting system, as described by the NRA, includes Fit, Form and Function, and Mounting. Each one of these designations has an impact on eye relief.
Why put so much importance on correct eye relief?
Setting the correct eye relief maximizes a shooter's magnification field of view. Seeing the fullest FOV downrange without darken circles around the lens dramatically improves accuracy.
What Is Eye Relief?
A simple explanation of rifle scope eye relief; the shooter is in the firing position, with cheek weld comfortably sitting on the rifle stock. The shooter is looking through the ocular lens of the rifle scope.
From the shooter's eye to a full picture of the target is, you guessed It, eye relief.
If your eye relief is too short, the shooter sees a dot in the middle of the ocular lens. Too far, and the picture is fuzzy.
Industry-standard for rifle scope eye relief is 3 ½ inches.
Until recently, the standard was fine on 9x scopes. Downing a trophy buck involved short distances with average to light loads. Only hunters with resources could afford the elite scopes needed to hunt big-game.
The market today is filled with affordable precision optic scopes with magnification ranges above 20X. Scopes from Nikon and Vortex feature a line of high-end rifle scopes with magnification ranges of 24X, 35X, and 27X.
Add to that, Magnum cartridges by Weatherby and Winchester and hunters are faced with a recoil beast.
Every rifle scope model in the world has a designated optimum eye relief. Shooters need to know this number and what game they hunt. Or they risk the dreaded Scope Eye. Many hunters believe the standard distance should be moved out to 4 ½ inches due to the rapid development of Bigger is Better attitude.
Eye Relief Scope Chart
Eye relief scope charts can vary depending on the manufacturer and model of the rifle scope. The information provided on the chart typically includes the eye relief distance for each magnification setting and the range of eye relief distances for the entire magnification range of the scope.
Some eye relief scope charts may also include additional information such as the diameter of the eyepiece lens and the exit pupil size. The diameter of the eyepiece lens is important because it can affect the size of the exit pupil, which is the circular beam of light that exits the eyepiece and enters the shooter's eye.
A larger exit pupil can make it easier for the shooter to align their eye with the scope and see the full field of view.
Eye relief scope charts may also vary in the units used to measure the eye relief distance. Some charts may use inches, while others may use millimeters.
Additionally, some manufacturers may provide a more detailed eye relief chart or a more simplified version. A detailed chart may include specific eye relief distances for each magnification setting and any changes in eye relief that occur when adjusting other settings such as the diopter or focus. A simplified chart may only provide the average eye relief distance for the entire magnification range.
"Ultimately, the specific information provided on an eye relief scope chart will depend on the manufacturer and the model of the rifle scope. "
It is important to consult the manufacturer's documentation and perform your own testing to determine the appropriate eye relief for your individual needs.
Concepts That Affect Eye Relief?
Magnification
When a shooter views their target through a rifle scope, magnification changes the perceived distance as compared to what is visible by the naked eye. More magnification does not ensure a higher level of accuracy.
However, the greater the magnification, the further away your target can be viewed with accuracy.
Typically, the higher the magnification a rifle scope provides, the shorter the eye relief. This correlation can be a significant issue if the hunter is using high-recoil magnum shells.
With lighter loads and shorter distances, eye relief will not be much of an issue.
Magnification
When a shooter views their target through a rifle scope, magnification changes the perceived distance as compared to what is visible by the naked eye.
More magnification does not ensure a higher level of accuracy. However, the greater the magnification, the further away your target can be viewed with accuracy.
Typically, the higher the magnification a rifle scope provides, the shorter the eye relief. This correlation can be a significant issue if the hunter is using high-recoil magnum shells.
With lighter loads and shorter distances, eye relief will not be much of an issue.
What is Exit Pupil
When you have a properly balanced and level rifle scope, looking through the ocular lens should produce a clear, round, and full picture of your target image.
The scope projects your target image through the ocular lens toward your eye in a cone shape. The further out the image travels, the larger it becomes until it reaches optimal size.
The distance is eye relief, and the image is the exit pupil. Larger exit pupils are more forgiving and provides more light.
The pupil of the human eye is between 2mm and 7mm in size. To calculate the size of an exit pupil image, take the diameter of the objective lens and divide it by the magnification. In a perfect world, the exit pupil should match the size of your eye pupil.
Here is the tradeoff: If the exit pupil is much larger than your eye pupil, light is lost and provides less picture. In low-light conditions or higher magnification settings, a better quality scope with a larger objective lens would be a better value.
Quality scopes with multi-coated lenses and higher percentages of light transmission will outperform lesser quality scopes with the same objective lens. Better quality allows the scope to be mounted further away and return the same quality optics.
5 Optical Elements In A Long Eye Relief Rifle Scope
Magnification
is critically important when purchasing a rifle scope. Remember, your eyes are closer to the scope with higher magnification levels.
If you plan on hunting big-game with long-range precision targeting, magnification becomes even more critical to your success. However, big-game, magnum cartridges, and powerful rifles equal substantial recoil.
Most experts agree; eye relief on powerful setups should be at least 5 inches at the lowest magnification setting.
The Reticle
is critically important for accuracy and a successful hunt. The aiming point should give adequate information, adjustment, and holdover positioning for a good idea of the bullet's trajectory.
Optics
are an essential asset in the quality of a rifle scope. Lenses should be anti-glare and multi-coated. They should transmit as much light as possible to give the shooter a clear, crisp picture of the target. Optics should provide the ultimate contrast in low-light situations.
Diopter Adjustements
Diopter Adjustment is used only for focusing the reticle. Never use the Diopter to focus on the target.Diopter adjustments are similar to windage, adjust once, then leave the control alone. If your scope is equipped with Diopter, look through the scope at a plain colored background, around 20 feet away.
Adjust the Diopter until the reticle is clear and perfectly in focus.
Parallax
is the most complicated and confusing adjustment to new scopes. A parallax error means the reticle and target are not on the same focal plane. In other words, the target looks like it is in 3D.
Scopes equipped with parallax turrets control the issue quickly.
For most hunting environments, parallax issues are negligible.
A Quality Rifle Scope With Long Eye Relief
UTG 2-7X44 30mm Long Eye Relief Scout Scope. The UTG is an affordable scope with excellent characteristics. Any hunter going for light to medium weight game should consider this scope. The UTG has a good magnification range for a variety of hunting conditions.
The UTG features nearly 11 inches of eye relief.
Another useful feature is the option to customize the reticle. UTG gives you the option of choosing from 36 colors or customize to surrounding conditions.
One of the best options for the UTG is the Zero locking and Zero resetting features. Put your Zero in place at whatever yardage is comfortable and lock it in place. You now have your standard Eye Relief.
If the Zero goes out of place hit a button, and it is reset.
How Far Back Should I Mount My Scope?
The first rule of thumb, when fitting a scope, "never alter the shooter's position" Moving the firing position forward or back to accommodate the scope, draws them out of their comfort zone.
This unnatural positioning leads to loss of accuracy and missed shots.
Precision Fire from YouTube gives the Viewer an excellent presentation on adjusting for eye relief BEFORE installing your rifle scope. The video stresses, take the time to establish your optimal position. If you take the time it makes all the difference in the world to how your accuracy and efficiency improves.
Mounting a rifle scope for proper eye relief is a straightforward process. Always leave room for play and adjustment later.
Conclusion
Remember the good ole days when hunting was throwing the rifle in the back of the truck and heading for the hills. Little to no consideration was given to the technologies of the day before the hunt. Quite frankly, there weren't any!
Modern hunting is so much more fun and engaging, now that technology has taken a firm hold on our equipment. The great component of all the breakthroughs in precision optics, rifle materials, and long-range ballistics is the opportunity to be extremely accurate. No more aiming for the right side of the animal. Accuracy has allowed elite shooters to target precise areas, no more than two inches at several hundred yards.
No longer do elite marksman shoot from the hip. Trajectories, bullet drop, and ballistic charts are available for every cartridge and rifle made. Eye relief and exit pupil are now accounted for and studied by inexperienced to the elite. The more eye relief and exit pupil have been analyzed, experts have agreed; these small intangibles are fundamental ingredients to precision accuracy.
Every scope and firearm builder in the world have begun adjusting to the new normal in hunting, precision accuracy, and the elite shooter. Trends are followed for long-range hunting and competitions.
Ballistics, like the 300 Weatherby Magnum cartridge, has been available for over 50 years. Only recently are the firearms been around to take advantage of the firepower.
All the technology boils down the image the shooter sees from their ocular lens mounted on the rifle. Once the ramifications of eye relief are understood, elite shooters will keep those 3 to 4 critical inches in the back of their minds forever.
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