Holosun HE515CM-GR Elite:  Review

In the world of budget-friendly red dot optics, there are few companies that match the level of innovation, quality, and variety that Holosun has achieved in recent years.  From their HS510c reflex site (which looks like a cross between an EoTech and an RMR), to their new HS509 enclosed pistol reflex site, to their wide line of Aimpoint micro-like red dots - Holosun has made a name for themselves as an industry leader in affordable and reliable electro-optics.

I reached out to Optics Planet recently to inquire about a Holosun optic that had recently caught my attention, as I was looking for a more affordable Aimpoint T2-like micro dot that would work atop another great product I’d picked up recently - the Unity Tactical FAST mount.  The optic I decided on was the Holosun HE515CM-GR Elite

First though, a quick overview of the 515 models’ various designations.

First letter “C” designates the models with a solar panel, side brightness buttons, and battery tray

First letter “G” designates the models with no solar panel, top brightness buttons, and battery container on the side

Second letter “M” designates the models with an aluminum housing

Second letter “T” designates the models with a titanium housing

“-GR” designates the green reticle models

“-RD” designates the red reticle models

The Holosun 515-series optics are marketed as being “Military Grade” optics - which is a designation given to them over the more lower priced Holosun models for the following reasons:

1. Housing material:  The 515cm’s housing is made of stronger and more stress resistant 7075 T6 aluminum, instead of the softer 6061 T6 aluminum of other models. Additionally, the ‘CT’ model is made with a titanium housing instead of aluminum.
2. Surface treatment:  The 515s’ housing surfaces are hard anodized, which creates a harder and more wear-resistant coating, whereas other models use the cheaper method of micro-arc oxidation (MAO) coating.
3. Submersion / Waterproofing:  The 515s have a IPX8 submersion rating, which means they’re rated for continuous submersion in water over 1 meter; whereas less expensive models like the 403-series have an IP67 rating - allowing for only temporary submersion in water 1 meter or less.

All said, the 515s have a higher build quality and are just generally built to survive more abuse than lower-end red dots. Whether they would hold up to the same amount of abuse an Aimpoint could take is unknown to me, but I feel confident they could stand up to an above average level of abuse.

What the HE515CM-GR Elite does boast over an Aimpoint, which along with the lower cost may make it worth it to you over an Aimpoint T2, is features.  The HE515CM-GR Elite, like most of Holosun’s product line, is jam packed with features for such a small and simple little thing. Some of those features include:

1. Solar Failsafe panel:  On the top of the 515cm you’ll find a small solar panel which serves as an auxiliary power source for the dot when any bright enough light source is overhead. This helps in the preservation of battery life, especially when outside in daylight, however the unit cannot run solely on solar power, and still requires a battery to function.
2. Shake Awake technology:  Unlike the Aimpoint T2, which is either on or off depending on where the dial is set - the 515cm will automatically turn itself off when it detects no movement for a certain amount of time. Upon being disturbed it will instantaneously turn itself back on - another battery saving feature. 
3. Reticle versatility:  On the 515 the user can select one of three reticle options. Either an EoTech-like 65 moa circle with a 2 moa center dot; the 65 moa circle without the center dot; or the single 2 moa center dot without the 65 moa circle.  Selection is achieved by holding down the (-)minus brightness button for several seconds.
4. Reticle color:  You can purchase the 515cm with either a green or red reticle. A note on why one would want a green dot over a red dot:  It really comes down to personal preference, and what your eyes and brain pick up and perceive more easily in different lighting conditions and different environments.  The only way to know is to experiment, but unfortunately the reticle color can’t be changed. You have to either but the green one or the red one. 
5. Auto-brightness feature:  The feature no one likes or uses from what I can tell - you have the ability to turn on or off a feature that makes the dot brightness automatically adjust to the light level of where you’re at, via the solar panel.  The problem with all auto-brightness optics (which include non-electric versions like the fiber optic Trijicons) is that where you’re shooting TO may be lit differently than where you’re shooting FROM.

Aimpoint T2 vs Holosun 515 - What’s the same:

1. Both use a CR2032 watch battery as the primary power source.
2. Both boast a 50,000 hour battery life (though with the 515’s battery saving features like the solar panel and shake awake feature, the 515 would most likely outperform the T2)
3. Both have “ramps” machined into the housing aside the fore and aft of the windage and elevation turrets, which are there to protect them from damage. 
4. Both use the same mounting footprint, which allows for use on a wide array of aftermarket mounts by numerous manufacturers.
5. Both have night vision settings that dim the reticle down low enough to not be too bright when looking through NVDs.
6. Dimensions and weight are close enough to where I’d consider them as being the same, and both use a 20mm optical window.
7. Both have a 2 moa center dot

Holosun 515 PROs:

All said I’ve been extremely impressed with the HE515CM-GR Elite in the time I’ve had it.  The glass is crystal clear, and has no color distortions. It comes with see-thru flip lens covers (which are very good quality and add protection and functionality), as well as coming with a kill flash (which I omitted).  It’s held zero perfectly; I’ve found the green reticle is easier to pick up in daylight than a red one; it’s about as robust and well built as you can ask for; and all the features along with being half the price of a T2 make it worth it to me over the Aimpoint for the build I have it on.  That said, everything has it’s downsides, and the 515cm-gr is no exception.

Holosun 515 CONS:

The fatal flaw that the 515-series has in my opinion is where the battery goes on the ‘C’ models.  Because there’s a solar panel on the top of the ‘C’ model unit, the brightness buttons had to be moved to the right side where the battery compartment on most Aimpoint-like red dots is located.  Because of this, Holosun had to move the battery to underneath the unit, which causes several issues:

1. The battery tray is a poor design:  The battery is held in with a waterproof tray that is slid into the right side of the unit and held in by two small screws.  The tray however is not designed very well.  It is too easily inserted upside down, and is very difficult to remove when this happens.  The tray should have been designed in such a way to where it’s impossible to insert when inverted.  Additionally (and this is a problem with many Holosun models that use a battery tray), the small screws that hold the tray into the unit can fail in several ways.  A) They can be lost when needing to change the battery in the field.  B) They require a tool (which can be lost) when changing the battery in the field. And C) the screws are small and weak enough to where the head of the screw can be snapped off by even slight over tightening.  This will cause the shaft of the screw to be stuck in the body of the unit, with no way of getting it out in the field, and thus no way of properly securing the battery tray back into the unit.  None of this should be acceptable on an optic marketed as being ‘military grade’.
2. Increased window height.  When Holosun  stuck the battery tray under the unit, this required that the optic windows be raised a few millimeters to accommodate the battery. The problem with this is that when used with standard height (absolute or 1/3 co-witness) aftermarket mounts, the 515s’ lenses will not line up where they would normally be, which affects the ability to properly co-witness iron sights or use a magnifier.  Holosun tries to fix this issue by including a proprietary mount (that is slightly shorter to account for the increased height) that ends up bringing the unit back to standard height.  The problem with this though is that most consumers opt for aftermarket mounts of standard heights over the lower quality mounts the Holosuns come with.  

Now, you might be saying “Thanks for the info, Rob, I’ll just go with the ‘G’ model 515s with the battery compartment on the side then, and avoid those issues.”  Unfortunately, even the ‘G’ models suffer from the increased height issue, even though they don’t have a battery underneath the unit, and thus no need to be higher than standard.  Why’s that?  My guess is that for production reasons Holosun didn’t want to have to machine two different bodies for the 515s, and decided to just make them the same for simplicity.  My recommendation (and if I were to do it again) would be to get the ‘G’ model to at least avoid the battery tray issue, which is much worse than having a slightly higher optic on a standard height mount. 

All of these issues are really the result of one thing: Buttons.  Had Holosun used a brightness dial with the battery compartment built into the dial (similar to the Aimpoint), they could have avoided these issues, while still having the top solar panel - which is the more unique and practical feature of the Holosuns that set them apart from Aimpoints and other brands. 

Lastly - to kick more sand in the face brightness buttons - I have found I really really dislike buttons.  They work on the RMR because they’re larger, impossible to miss (as they encompass the whole sides of the unit), and the (+) and (-) are on opposing sides instead of side by side like on the 515 (and, there’s no other option for an RMR).

If a solider bursts out of a dimly lit building onto a bright sunlit street he may find the need to quickly increase the brightness of the reticle on the optic, and with fine motor skills gone that is a challenge with the button set up on the 515.  It is too easy (even when not under duress) to miss the buttons, or hit the (-) button instead of the (+) when trying to change the brightness setting, given that you can’t see the buttons on the side of the unit from behind the gun, and it’s not easy to feel the difference, and is even more difficult with gloves on.  The dial system is simply a better design, and more suited on a ‘military grade’ optic.  

Buttons and battery trays aside, the Holosun 515 is an excellent optic, and well worth the price.  If you’re looking for the closest thing to an Aimpoint T2, but at half the price, any of the 515 models would serve you well - but again, I highly recommend getting the ‘G’ models over the ‘C’s.   If you’re in the market, check one out from our partners at Optics Planet and use code ARMSLIST for 5% off any order!