The first time a low power optic appeared on the sport shooting market, the tactical world took notice. A sighting device that superimposes a reticle on the target would make shooting faster. The quantum leap to low power optics in law enforcement did not take long.
Low power optics are slightly or non-magnified optical devices designed for binocular or occluded vision sighting. This class of optics includes reflex type sights, holographic sights and 1-3x scopes. These products are designed for sighting with both eyes open while one eye looks through the device. For police work, optical sighting devices should be mandatory.
Low power optics generally mount directly to picatinny rails like the EOtech HOLOgraphic sight or use standard scope tube diameters like the Aimpoint Comp Series sights. Their reticles can be dots, suspended crosshairs, triangles or a combination of shapes. The aiming dots are generally larger than 1 MOA (minute of angle) and rarely get larger than 5 MOA, which means they cover about 1 to 5 inches of a target at 100 yards. For most products, the size of the dot cannot be adjusted, although the intensity can. The dots are adjustable for windage and elevation, usually in coarse increments of 1/2 MOA per click.
Low power optics are appropriate for use at any distance one would normally employ a traditional iron sight. Although the shape in the viewing window is almost always bright enough for use in direct sunlight, it is invisible from the muzzle side, even in the dark. Their concept may be simple but the technology behind them, especially the holographic technology, is cutting edge. Once sighted in, anyone can pick up an appropriately equipped firearm and use it. For the officer who goes from gathering information during an investigation to gathering suspects after breaching their entryway, the ability to adjust the stock without having to adjust the sights is enormous.
In combat shooting, several events take place before accurate fire can be commenced. The officer sees the threat, recognizes it and orients. He aligns the sights to the target and responds — whether to fire or hold on target. Succinctly; see target, orient to target, align sights, engage, remove vision from sight alignment to scan.
With iron sights, the shooter sees the target and moves the sights into the field of vision. With low power optics, the shooter keeps the gun in "ready to fire" position and the "bullet will strike here" display stays in his view. There is no loss in peripheral vision. The shooter is no longer scanning over the sights. He is using the sights to scan. Vision and engagement are fused. Succinctly; See target, engage, scan, engage.
Types of sights
Iron sights can only be viewed or accessed from a single ray in space — one that begins from the retina and continues through the rear and front sight. Low power optics can be accessed from a zone that, as long as the retina accesses the image in this zone, the shot is successful. This means the officer can pull the trigger with a less than perfect cheek weld and still deliver aimed fire on the target.
Although using optics has distinct advantages, they are not a cure-all. They are designed to increase the rate of accurate fire, not accuracy. Battery-dependent ones have obvious weak links — capturing an LED or laser image needs batteries to create that dramatic floating image effect.
Optics get dirty. One must clean them with the same care as any other optic. That is, blow them off first, then brush, if blowing doesn't work. Clean them with a more aggressive method only when necessary. Nearly every product has some anti-reflective/maximum transmission coating. Users must take care not to scratch this coating.
One of the advantages of the low power optic is the ability to accept tremendous variances in the eye relief. A sight can be mounted close to the eye or further down the receiver to accommodate for night vision accessories and magnifiers. Most are compatible with night vision and thermal viewers. They may be coupled with a night vision monocular, binoculars or rail-mounted scopes.
A reflex type optic generally uses an LED for the light source of the dot. This type of sight reflects light off a specialized mirror that reflects a narrow bandwidth visible to the shooter.
Imagine a person sitting in a living room next to a reading lamp at twilight. A window is nearby. One can see the reflection of the lamp in this window. If a person was outside, the seated reader could put the reflection of the reading lamp on that person's forehead and cause that reflection to follow the outside person around.
The reflex-type sight works on the same principle, only the reflective surface travels with the shooter and the outside person cannot see the lighted living room. Aimpoint uses an LED to power its red dot in its COMP M2, called the M68 CCO when used by the U.S. military, including Special Forces. The 300,000 or so currently in service is a testimony to the reliability of the Aimpoint system.
A holographic sight coincides a visible laser hologram with the "real world." Essentially, it records a 3D image and reconstructs it on the target plane. To the user, the holographic image is painted on the target, parallax free. Through the EOtech Holographic sight, one literally sees the floating reticle on the target. The 3D quality is quickly evident when the shooter shifts the position of his head. As long as the target is "painted" within the sighted range of the system, it can be engaged.
This kind of sighting defies the imagination. The concept of "wavefront reconstruction process" is a product of scientists making science fiction into reality. They combined the technology into a compact waterproof package and made it run on common batteries.
Where would the holographic sight be most advantageous? Answer: In a target-rich environment. The user can maintain a sight picture on the most immediate threat and monitor incoming threats. An EOtech-equipped soldier on the battlefield can rapidly sort and engage targets. An officer sweeping for an armed suspect can maneuver and see the sight at the same time.
How long do the batteries last? Some low-power optical devices can be left on for months without a battery change. They are not expensive to use and can be "press checked" thousands of times without a failure. Trijicon uses TriPower platforms which incorporate fiber optics, tritium and battery power in the same unit while the Trijicon Reflex optic is dual illuminated. Aimpoint reports about 10,000 hours on the daytime setting.
Still, they should never be used without a co-witnessing sight system. The units may be shock resistant, but batteries do not come with the same warranty. Carry extra batteries and mount iron sights. GG&G has designed flip-up sights that are out of the way until needed and maintain their zero. They also have designed a cantilever mount for the Aimpoint Comp M2 ring for an extra battery.
Co-witnessing
If the user has flipped up the front and rear sight, the dot or aiming point of the optic will align with the front sight. That is, a rifle sighted in with iron sights will coincide with the aiming point of the optic. For red dot optics like the Aimpoint Comp M2, the dot should look like it is sitting on the front sight post.
This is called co-witnessing, an indication the optic is sighted correctly. Iron sights should coincide for the same distance and conditions. When adjusting the optic and sights for co-witnessing, don't worry about centering the dot (crosshairs, triangle) in the optic, just align the sights with the dot. The red dot really doesn't have to be centered in the optic — it just has to be visible. Co-witnessing works best when the flip-up sights use the bottom third of the optic. This ensures that the optic has an iron sight back up or confirmation when needed.
Practice
Shooters used to conventional sights will need to train themselves to keep both eyes open when shooting. Use reactive targets like steel speed plates or falling head plates that deliver a loud reward when hit. Set up at least six reactive targets per shot string and mow them down. Practice flowing from one target to the next without allowing the eyes to leave the sighting axis. Change the distance between targets and reshoot the plates.
The cheek weld is different using an optic. Shooting plates will get the shooter to instinctively use the correct head position. The head position can be reinforced by shooting plates out to 100 yards using deliberate trigger and breathing techniques. This will also give the shooter an idea how large the dot or reticle is at this distance.
Practice 100-yard plate shooting by moving toward the plates without allowing the sight to stray off target. While moving, concentrate on establishing shooting platform, breathing and squeezing the trigger.
A low power optic is the best addition to the law enforcement carbine, less-lethal or shotgun platform an officer can purchase. An optic increases the usability and efficiency of any CQB (close quarter battle) system. The optic/carbine combination should be in every unit. What should we expect in the future? Sooner or later, someone will make a holographic system that does not need any glass or sighting body to project the sight.
Lindsey Bertomen is a retired police officer who teaches Administration of Justice at Hartnell College in Salinas, California.