EOTech or Electro-Optics Technologies, Inc. is based in Ann Arbor, Michigan. EOTech designs and manufactures advanced laser and holographic products for military and recreational sport applications. EOTech has developed products used in military, law enforcement, recreational sport shooting, golf, and now archery. They have been developing products for the military, NASA, and intelligence groups for over five decades. Bottom line is, these guys know their stuff when it comes to engineering and developing advanced sighting systems for tactical weaponry and firearms. When we contacted Van Donohue, EOTech owner and Marketing Manager, the next thing we knew a model 520 with RH mounting bracket was on its way to BowCountry.com.

How the 520 works
By adapting Heads Up Display technology (H.U.D.) similar to that found on todays fighter jets, EOTech has developed a state of the art hunting sight. Let's first discuss how this high tech accessory works.

The EOTech Holographic sight produces a three dimensional (3D) reticle pattern consisting of two rings that are projected in a confined space and between the small panes of glass within the housing of the 520. The images projected within the panes are at two different distances from the shooter but within the sighting unit. The near image is at five feet, the far image appears to be at the target plane. The images have the same effect as a front and rear sight, (peep and pin) except that they are floating in space. Since the targeting reticle appears to be projected onto the target, the sight radius is equal to the target distance, and we all know (least I hope we do) the greater the distance from the peep to the pin means greater accuracy. Here's simplicity in action: EOTech recommends keeping both eyes open, position the laser dot on the target, align the reticle rings and wha la!, a perfectly centered shot. Let er rip! Enough on the EOTech Model 520 theory and the physics involved, lets see how it performs in the field and on the range.

Performance and Quality
We immediately checked our EOTech 520 Holographic sight and bow mount for defects in workmanship. We looked at the overall appearance of the Holograpic 520 sight and HHA mount. Usually first impressions tend to stick with you, and this was no exception. Amazingly, we found no defects (we can usually find something).

The all aluminum adjustable mount made by HHA comes with ample adjustability for even the shortest sight windowed bows. The mount comes equipped with nylon bushings for a tight, smooth feel during adjustments.

Installation of the mount on our SQ2 test bow was very straight forward and simple. The only tools required were two allen wrenches and they were supplied with our sight and mount. After installing the mount we mounted the supplied Weaver rail that will be used for front to back adjustment on the Holo Sight. Once we mounted the Holo Sight on the weaver base, we needed to draw the bow to see how the site lined up with our eye using our already established anchor point. One thing you'll want to do is keep the sight as close to the riser as possible or your anchor may have to be adjusted to match. It took a little adjusting to get the whole recticle in view but if you follow the provided directions, it won't be overly complicated. One very important point here is we do not feel the average "Joe" should be messing around trying to calibrate and rough sight this product. One of our senior staff writers took a full two days of messing around just to get this sight shooting straight from 10 yards. Even Van Dononhue, of EOTech, suggested this was not something you'd want to tackle on your first go around with the product. In other words, this isn't a pin sight and peep arrangement!

Sighting in the Holo Sight was fairly easy. Once we got it within four inches of our bullseye we used the windage adjustments on the Holo Sight to fine tune our point of impact. Major disappointment here, in that the windage adjustment was nearly impossible with the 520 mounted. If you can contort your fingers appropriately and manipulate a dime (which is the only object with a low enough profile to fit in between the riser and scope) then you'll be all set. One of our staff shooters found it easier to take the entire scope, weaver rail and all, right off the HHA mounting bracket. Not good. Not good at all!

Once we zeroed our sight, we sighted our Holo Sight in at forty yards. With the short sight window on our Mathews SQ2 test bow, and the bottom of the sight dangerously close to the blades on our broadheads, we couldn't go much farther than that. This was major bummer number two, after the nearly impossible access to the windage adjustments. Due to the fact that there is almost 2 1/4" from the bottom of the sight to the center of the reticle the fear of a broad head catching something on the riser exit was very real and very palpable.

If you shoot mechanicals you have nothing to worry about. If you shoot something like a Bob Foulkrod Titan you should either up your insurance policy or simply buy another product!

Once we sighted our 520 in, we took it to the 3D range to really put it to the test in simulated hunting scenarios. The first target we came to was out in a open grassy field. We pre-sighted our SQ2 and came to full draw. That's when some of us noticed bummer number three. There was no sun shade over the lenses and anyone that has ever shot with a scope outside on a sunny day knows exactly what some of us saw. The whole target disappeared in a flash of sunlight. After a few minutes fashioning a make shift sunshade (our buddy holding his hat over the lenses) we were back at it. It's also important to note that, some BowCountry.com staff shooters simply boosted the contrast button on the sight and managed to overcome this "glare out" phenomenon.

We got back to the test. One very nice aspect touted in the EOTech marketing and absolutely true in the use of this product, is we were able to visually gauge how much we torqued the bow before the shot. The double reticle design of the EOTech 520 is able to provide instant feedback, before you release the shot, by viewing how the reticle circles are lined up. Believe us, it doesn't take much grip pressure. To our knowledge there is no other sighting system on the market that provides this kind of visual feedback. A few targets later we were into the woods and able to lose our makeshift sunshade.

In normal or low light conditions the Holo Sight 520 really excelled. The Holo Sight works phenomenally well in low light conditions, but you will find it necessary to keep the sight contrast button on the lower end of its lower setting so the lit reticle doesn't overpower the target. Too bright of a sight creates fuzzy reticle rings and can be just as bad as dead batteries.

The sight performed very well in dark woody conditions, where a peep and pins would be almost impossible to see. For the magic last few minutes of daylight, this can mean a world of difference. Keep in mind, all you ethics watchers, it was only late afternoon still well within legal shooting hours. Since the laser does not project directly on the target, and is contained in the heads up display unit within the scope, we can't imagine there would be any legal issues in most states.

The repeatability of the sight was great, until two allen screws on the bottom of the weaver rail mount loosened up. Once we tightened the screws the site came right back on target. We would definitely recommend a thread locker to prevent this from happening to you. The last thing anyone wants is a loose sight screw when you are staring at the biggest buck of your life!

The left/right adjustments of the HHA mounting bracket leave a lot to be desired. There are fixed, countersunk, predrilled, holes that are equidistant apart, so if you just so happen to want something in between, too bad! At one point, one of our testers actually loosened the allen screws beneath the weaver rail and obliquely angled the entire scope unit to get the appropriate adjustment. In our professional opinions, the HHA Mount was poorly designed, way, way heavy, and definitely reduced the enjoyment of the EOTech 520 significantly.

Cool Range Finder
A real nice feature is the built in range finder. By angling the bow slightly sideways while looking through the archer side reticle, you'll see a heads up range finder on the right hand side calibrated to the average body deer. Using the back and belly lines of the average deer (16") you can reasonably guesstimate how far away your prey is, out to sixty yards. We hesitate to call it a range finder in the Nikon or Bushnell sense, but in general, we are all for taking out the guess work when it comes to judging yardage. Unfortunately for you 3-D shooters, this also makes the sight illegal to use at your local 3D tournament, so order the 520 without this option.

Summary
The EOTech Holographic sight may be a little pricey at $329.00, but it is packed with features that only the die hard pin shooter could ignore. The built in ranger finder is a hunters dream come true and the peep eliminating dual reticle system is better than sex to a swamp hunter, where dark shadows are the rule of thumb.

There are four (4) major drawbacks; a poorly designed and possibly dangerous HHA Mounting bracket could cause disastrous consequences depending on your broadhead of choice, nearly inaccessible windage adjustments on the right hand model we tested, "glare out" phenomenon in extreme bright light conditions for some caused the desired target to be obscured with glare, and the overall weight, according to our postal scales, 14+ ounces with bracket. Ouch!

We also felt that a down side to the EOTech 520 sight is the fact that you can't use it as a dual-purpose sight for hunting and 3D because of the built in range finder. Sure, you could buy the 520 without the optional range finder, but this means if you want to do both 3D and hunt you either get two bows or constantly switch sights back and forth.

It may not appear as such in this review, but we really, truly, like the 520. It is a product too far ahead of it's time right now, but, hopefully, with feedback like this and Tom Miranda demonstrating the 520 on a successful Northern Black Bear hunt, the 520 is bound to overcome it's deficits. Engineer a more flexibly adjustable mounting bracket, lighten the entire system, and accommodate a more diverse set up and the 520 will become a standard for some. "Times are a changin" and the radical technology is slowly working its way into the archery industry. If EOTech Model 520 Holosight is a sign of what's to come, then the future of archery is looking great.

All things considered, this rugged unit, which the manufacturer says has been shock tested by dropping from a tree stand, needs very careful scrutiny before any archer considers a purchase decision. We rate the EO Tech Model 520 Holosight sight 3 stars on a five star scale.

For more information on the Holosight from EOTech you can check out their website at www.eotech-inc.com

Our very sincere thanks to Mr. Van Donohue of EOTech for participating in BowCountry.com's "Test and Tune" !