Shooting with both eyes open is not only possible but gives the hunter a big advantage for fast shots at both close and medium ranges.
“This is where they’ll be, so keep your eyes peeled!” Isn’t that the sort of thing we say when there is a chance of seeing a big mob of ‘critters’ or a trophy ‘beastie’? We say eyes, which is plural. So why do we look with two eyes, yet shoot with only one? Why don’t we use both eyes open shooting techniques? Of course, if the target is a long way off and there is no urgency, using only one eye is not a problem for effective shooting but when walking-up or stalking game, whether it is the humble rabbit or the mighty elephant, closing one eye to take the shot is a serious handicap to impose upon ourselves. So why do we do this to ourselves, why do we shut out so much of our sensory input at the most critical moment of the hunt?
Table of Contents
Human Vision
The human eye is a very effective sensory organ and, for us hunters, it is the most significant. By comparison, our sense of smell and our sense of hearing are poor, particularly when compared to the animals we hunt. To help compensate for this shortcoming, nature gave us two excellent eyes and, like other primates and predators, our eyes are located in the front of our heads. This gives us good binocular vision which extends for around 140o while our peripheral vision extends another 30o either side for a total field of view (FOV) of 200o.
The anatomy and geometry of our eyes provide clear advantages and human daytime vision is superior, to daytime animal vision, in several ways; our binocular vision is wider, our colour range is greater, our depth perception is superior and the images we see are much clearer and sharper. Of course, at night, we are practically blind but that is the price we pay for excellent daylight vision. At the same time, prey don’t need a crystal clear, full colour image of a hunter to dodge a bullet or to avoid teeth and claws. They only need to detect something suspicious, through sight, smell or sound, and they will revert to survival mode. The animals we hunt, despite our excellent eyesight, have a clear sensory advantage over us.
Field of View
If we then consider that the FOV of the average riflescope is only around 10o we can see that, when we shoot with one eye closed, we are depriving ourselves of as much as 95% of the hunting scene before us. So why do hunters sacrifice their only sensory advantage, their vision, in preference for a limiting 10o FOV? The answer is that we were all taught to shoot with one eye closed because gun-sights, till now, required us to shoot that way. However, as we have already seen, closing one eye and squinting through a scope tube, is a self-imposed handicap of a significant magnitude. It is true that we only impose this handicap for a very short period of time, and maybe only seconds, but nature is unpredictable and a lot can happen in that time.
Military and Law Enforcement
Many military and law enforcement agencies have learnt the both-eyes-open lesson and now teach their members to shoot this way to increase their combat effectiveness. On today’s battlefield, the ability to see and detect both threats and non-threats, and to accurately engage the threats, throughout 360o, is crucial. For a soldier, or policeman, to be able to see, with weapon ready, everything with just small turns of the body, can mean the difference between a successful mission, going to prison for an unlawful killing or going home in a flag-draped box.
Hunting
For the hunter, it can mean the difference between an unsuccessful hunt, which may have cost many thousands of hard-earned dollars and a large portion of scarce leisure time, or hanging a new trophy on the wall or putting meat in the freezer. If we are talking about dangerous game, it can also mean the difference between a successful hunt and going home, chewed or stomped, in a shoebox.
Imagine, for a moment, that you have made a substantial dollar investment for the hunt of a lifetime. After days of hunting you spot a nice animal. It is not the trophy you dreamt of but it is the best you have seen. You stalk in, shoulder your rifle and close your non-dominant eye; your world shrinks to the size of your scope’s FOV. However, while you are taking up the trigger pressure, and concentrating on the animal in your sights, a record book trophy now walks out into the open, but outside your FOV, and presents itself for a once in a lifetime shot. However, with your vision restricted to a 10o FOV, you don’t know he is there. You cleanly take the smaller trophy, but your moment of triumph is shattered as you now watch a fantastic trophy run off, spooked by your shot.
In an alternative scenario, you have found a huge trophy and are about to take the shot. You have closed one eye and your finger is on the trigger, but your quarry suddenly senses danger and runs. Now you are trying to make an aimed shot on a running animal through a 10o FOV. The magnified images, of the moving animal, that your brain sees through the small FOV are too complex to process properly so it is mostly blurred and indistinct. What you can see is something like; branches, bush, patch of fur, branches, bush, patch of fur. To shoot, when the fur is in your FOV, may be foolhardy because you really aren’t sure if you are looking at the input or output end of the critter; it is a very difficult shot to take with one eye closed.
Dangerous Game
Now, let’s consider that you are hunting dangerous game, perhaps a Cape buffalo in Africa or even a feral pig in outback Australia. You stalk in on an animal, close one eye, lose 95% of your vision, and you are suddenly charged by another animal that comes from outside your scope’s FOV. If you had had both eyes open, you would have seen him in your peripheral vision, but because you had closed one eye, you are effectively blind. You may hear him coming but, by the time you open both eyes and look for the threat, it may be too late and you could be injured or even killed and all because you shut down a huge part of your best sense; your vision.
These three scenarios, and many other scenarios just like them, can be overcome by simply shooting with both eyes open and today’s technology has given us the means to do this. With an optical sight, featuring a prominently illuminated reticule, shooting with both eyes open is relatively straightforward. Indeed, you can shoot both-eyes-open with any optical sighting system but, until the advent of illuminated reticules, this was still very difficult as the non-illuminated reticule is easily lost in the cluttered background image that you will see, particularly if shooting at moving game.
Illuminated Reticles
With a prominent illuminated reticule, the illumination will stand out against the background, so there is no longer a reason to close your non-dominant eye. With a prominent, illuminated reticule you can shoot stationary, moving, distant and close targets or game; just so long as the illuminated reticule stands out against the background. I said, above, that the reticule must be prominent and while a small dot, at the centre of a duplex or Mildot reticule can still be successfully used with both eyes open, it is obviously much easier to see a large illuminated reticule such as a dot, triangle, chevron, circle dot or horseshoe dot, of at least 4MOA in size.
Red-dot style sights, as made by almost every scope maker, are naturals for both eyes open shooting and most shooters are aware of this style of sight and the advantages of using them. However, red-dot sights all suffer from one serious limitation and that is that they are unmagnified; great for close to medium range shooting but limited over longer ranges or when looking for a target that is largely obscured such as a deer standing in a thick patch of bush.
To compensate for the lack of magnification some makers, such as Aimpoint, have introduced magnifiers that can be mounted in line with your red-dot sight to give you 3x magnification. While this system works, it has two limitations; firstly, there is the added cost of buying the magnifier and, secondly, there are problems with mounting it on a conventional hunting rifle. On a ‘Tactical’ rifle, with a long MIL-STD-1903 Picatinny rail, this isn’t an issue but try it on your ‘Remchester’ hunting rifle and there maybe nowhere to mount the magnifier. The other limitation is that you now have four (4) lenses to dissipate the light, as it passes through them, and those four lenses can also collect twice as much dirt and dust as a conventional scope.
Magnified Riflescopes
However, the best solution for both-eyes-open shooting is a magnified riflescope with a brightly illuminated reticule. Many riflescope manufacturers now make illuminated reticule scopes, from the expensive European companies, such as Swarovski and Schmidt & Bender through to the mid-priced scopes from Trijicon and Leopold and to the lower end of the market with illuminated reticules from Nikko Stirling and Tasco. Unfortunately, some of these manufacturers use relatively complex, illuminated reticules making them less suitable for both-eyes-open shooting as a complicated reticule can obscure the target with both eyes open shooting.
For my money a simple, small dot at the centre of the reticule is ideal. You can find this style of reticule in many brands of illuminated scopes, such as Leopold, Minox, Swarovski and Trijicon. An illuminated triangle, such as the Trijicon Accupoints use, is also an excellent both eyes open reticule. I am not so fond of the Schmidt & Bender Flashdot or Swarovski Circle Dot reticules as I think that they tend to obscure too much of the target, when shooting both eyes open however, that said, they will still do the job.
Some scope companies are now trying to push the advantages of both-eyes-open shooting. Schmidt & Bender advertise their Flashdot reticules for this style of shooting at 1.5x magnification and Trijicon have been promoting it for many years and they call this technique the Bindon Aiming Concept (BAC); named after Glynn Bindon who developed the technique. So how does BAC work? Well let us consider BAC shooting with one of Trijicon’s 1-4x scopes with an illuminated Triangle reticule. To start, turn the magnification setting up to 4x and leave it there. Yes, we are going to shoot both eyes open at 4x magnification and you can shoot with both eyes at much higher magnifications, too!
How ‘Both Eyes Open Shooting’ Works
If you are aiming at a stationary target then you will be able to process the visual information from both eyes. Your brain sees your usual unmagnified image (200o peripheral vision) but your brain also sees the 4x magnified image coming through the scope and your dominant eye. As the magnified image is stationary your brain is able to process all of this information and it simply forms a composite image of your 200o vision and the 4x magnified image. In this composite image, the magnified image will be prominent because it is coming from your dominant eye. So you will be able to take aimed shots at your target, showing in the magnified part of what you see, but you will also be aware of what’s in your peripheral vision.
However, if you are following a moving target, you will still see your usual 200o view but the 4x magnified image, which is also magnifying the movement, is too complex for your brain to process, so your brain automatically ‘switches’ to the 200o view. However, while the moving scene in the magnified view is distorted, and your brain largely ignores it, the illuminated reticule is not moving, within the scope’s view, so your brain still adds it to the composite image and you can clearly see it against the unmagnified view, which includes the target. Now you are using the magnified scope just like it was a red-dot sight.
Did you get the key point here? Your brain automatically does the switching for you. With just a little practice, your brain will learn to switch back and forth between dominant eye (magnified image) and unmagnified (200o) image, depending upon whether you are aiming at a stationary target or swinging your firearm as you follow moving game.
While the vast majority of shooters can master the BAC technique, once they are using compatible optics, there are some individuals who will find it a little harder to master. Most notably are those people who are cross-eye dominant, i.e. they are right handed but their dominant eye is their left, or visa versa. The simple solution to this problem is to learn to shoot on the side of your eye dominance; if you are left eye dominant then shoot left handed. Easier said than done, you say? True, but we can all teach ourselves to do almost anything if we really want to.
Prescription Glass Wearers
The other group of shooters, who may find it a little hard to master, at first, are those shooters who wear prescription glasses. I am 60, short-sighted and wear prescription glasses but, with just a little practice, I have learnt to shoot using the BAC technique and, now, choose to shoot with a BAC scope whenever I can. Very occasionally, my brain is a little slow in switching between the unmagnified and magnified views, but a quick little blink of my non-dominant eye, will wake the brain up and remind it of what to do. It is a sad fact of life that we all slow down as we get older but that doesn’t mean that we can’t learn to master new techniques!
Indeed, the BAC shooting technique, using a prominent and illuminated reticule, is the answer to most of the optical difficulties that are encountered by shooters who wear prescription glasses. When I shoot iron sights, as in Standard or Production Class IPSC pistol, Military Rifle or Big Game Rifle, I have a devil of a time getting my prescription glasses to work with a rear sight, a front sight and a target. However, give me a BAC-compatible scoped rifle or a red-dot equipped pistol or shotgun, and there are no hassles lining up the target with my aiming mark and, as a result, my shooting improves markedly.
Conclusion
Shooting, in the field and on the range, with both eyes open is logical and effective. Indeed, once you have tried and practiced it, you may have trouble closing your non-dominant eye again. So, the next time you squint through a conventional riflescope, while trying to take a shot at a moving or stationary critter, ask yourself these questions: Why am I closing one eye and shutting out so much of the scene before me? Why am I deliberately degrading my best hunting asset? Maybe it is time to upgrade my riflescope, join the 21st century and take back the advantage of having better eyesight than the game I hunt?
Remember, keep BOTH of your eyes peeled, even when taking a shot, and you will enjoy more hunting success.
Text and pictures © Robert Pretty 2016
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