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  • Ray Campbell

Holosun 510C: The Best Option For Longer Barrels Is Actually Affordable

Gun owners know just how important it is to have a reflex sight you can rely on, and I’m here to tell you that the Holosun 510C stands out from its competitors. These hands-on reviews will prove me right.

FYI, Prices and ratings are accurate as of time of writing.


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

Top-rated: 3,054 ratings | 286 answered questions


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

Highlight: The battery life can last up to 50,000 hours depending on settings.

Most helpful review: "I've had an RMR and a few Vorted red dots. The RMR had the dimming issue I resolved with an antiflicker plate and I loved it. The Vortex dots aren't sexy but they just work. I could punch a penny at 25 yards with both.
This new Holosun however beats them all. The features, construction, and options put it above the competition at almost half the price.
Perfect cowitness with the BUIS that came with my B&T GHM9. Took a considerable amount of left to right adjustment, but the up down was dead on.
The shake to wake feature gives it true "Go Gun" status. No fiddling with buttons to turn it on. In a bad situation you don't want to have to try to turn one on when you really need it. Pulling it out of your bag will bring it to life and you're ready to rock.
Autodimming is also a great feature my RMR and Vortex dots didn't have. Once enabled you will see a noticeable and immediate difference going from dark/dim to brighter areas. Works excellent outside. The feature is disabled by holding the + button for 3 seconds. This would be ideal if you're in a shaded environment and your target is outside in a brightly illuminated area.
In the higher brightness settings you can still see the reticle when you point it towards the sun. You won't lose your dot in bright areas.
The reticle options are also very hand. 2moa dot will help you plink pretty far down range and the larger 65moa reticle will give you fast acquisition at closer range. They definitely both have their place. And neither the RMR or Vortex dots offered multiple options.
The battery life is supposed to be incredible. I haven't had it long to know, but all testing has shown you'll have years between battery changes. Keep in mind it does come with a spare battery tray so you if your grip has storage you can keep the included torx tool and spare battery with you when it becomes an issue.
The solar feature is reassuring. Worst case scenario youre in the field or fight and the battery dies. If you are outside in the sun, or have enough ambient light the dot will still work. If SHTF and batteries are no longer available, you'll still be able to use it.
The value, man.. It is just a no brainer. Half the price of an MRO or RMR. More features. More rugged design. The Alamaba Arsenal torture test includes, pouring water on it, throwing it 20ft into the air and letting it hit the ground, freezing it in ice, beating on it, and SHOOTING it with a shotgun, and it still held zero.
The quick release mount also saves you an extra $150 if you were running other dots and allows for a perfect BUIS cowitness. Mine fit a little loose when I first installed it. I used the included tool and tightened the mount one turn and it clamped down with the force of an Amazonians thighs during Snoo Snoo. Absolutely solid now and still easy to release with the convenient latch keeper.
The picture is incredible. The thinner profile sides and large viewing window give a natural feel and you're not chasing the dot around. No toilet paper tube EFFECT or black glob in the corner like with the Vortex Sparc AR. With boys eyes open you hardly notice the frame. You just see everything as well as a dot in your FOV.
I will probably buy another one for my next Scorpion build. Can't imagine anyone coming out with a better optic for the money." — Marco Chavanne

Get it from Amazon now: $372.65


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

"I'll start out with the only negative and a disclaimer. The first optic I received from this seller was defective. It wouldn't project under normal daylight without the battery and would only work in direct sunlight. On top of that, there was excess glue, markings in the finish, and worst of all, you could see the square LED housing outline reflect off the glass which was very distracting.
With that said, these guys have the best customer service I've ever seen from any company I've ever had to deal with. I emailed them with detailed pictures of my issues, and less than 4 hours later they sent me a tracking number for the new optic. I received the new optic 3 days later with a return label for the old one.
The new optic is flawless. It is the best reflex sight I've ever seen, at any price point. Reticle is the sharpest I've ever seen on a reflex sight, gets plenty bright and I get zero parallax. This, coupled with excellent customer service make it one of the best purchases I've ever made. I'm really glad I went with this optic over the eotech i was looking at. It is honestly better than the eotech, and is half the price.
This is also one of the most technologically advanced reflex sights out there. The auto on feature has worked every time for me so far. It is sensitive enough to pick up you dropping the included torx tool on the table next to it. Sight will work without the battery provided there is any ambient lighting at all. You do not have to be outside or in direct sunlight. Auto brightness is a bit too dim for my liking, but it does work very well and adjusts instantaneously. I just wish it would be about 10% brighter in all conditions.
The only sight I've ever liked more, is the trijicon ACOG, but obviously that's apples to oranges. I would highly recommend picking this up.
Just for reference, if any of you are considering picking this up for a scorpion EVO, I think it fits it really well. I would probably go with a smaller optic if you're planning on keeping it a pistol, but if you're going to go with SBR route, it's perfect." — Alex

Get it from Amazon now: $372.65


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

"The product is well built and the quick release lever is great for mounting on the rail or dismounting quickly. Saw some reviews who said it didn't work out of the box. I did not have that issue. Installed the battery and it worked fine. The solar part kicked in as soon as exposed to light. The solar would likely work for most times but if you want a brighter circle, dot or both then power up the battery. It is adjustable and can go very bright. Also replacement batteries are like 5 bucks so no worry on that cost if you burn them up. I also like the auto off feature which you can adjust the time from 10 minutes on. It is a shake awake which literally just bump it and it goes on. I paired it with the Holosun HS3X scope and will be taking it out to zero in in the next week. I have confidence this will not be hard. Product appears built very well and after a few hundred rounds I'll do a follow-up review.
Well I took this out shooting the other day and I had paired it up with a Holosun HS3X magnifier in front of it. Worked great and allowed me to hit the targets with ease at 50 yards. Out of the box the height only needed slight adjustment. The wind I had to adjust to the right quite a bit as it was way off. Once I got it zeroed it was good to go. Went through over 500 rounds and it held zero the whole time. My son in laws tried it and they were nailing the target as well. Solar worked great and the red dot and circle were bright. My one son in law loved it so much that i Just ordered one for his birthday." — Mark Gerstlauer

Get it from Amazon now: $372.65


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

"I really like this red dot. Bigger than the RMR and cheaper. Perfect size for my AR pistol. Easily co-witnesses with the pop-up sights too. The "reflex" ability of this site is pretty great too. It turns itself off and then back on when you move the gun, saving battery. I haven't used the solar option, I set it for manual and use it on it's 2nd from the brightest setting. I've checked it on multiple occasions when the gun has been unmoved for 15+min, the red dot is off. Shake the gun or pick it up and the red dot is on. Then it goes back off once you leave the gun motionless again. Exactly what I was looking for." — DonSutt

Get it from Amazon now: $372.65


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

"The old adage - 'You get what you pay for' - holds true for this sight. I really tried to find a lower priced sight that would be "almost as good" as this sight. I'm not a fan of overpaying for something that's a couple of percentage points better. I believe that I will never regret paying the extra price for this sight. The construction of it is exceptional. I purchased it for my Ruger PC9 and it sits perfectly! The large screen (glass) is super easy to sight. I like the built-in solar array to support the battery (it doesn't charge the battery but the sight runs off of it instead of the battery in bright light). I also like the automatic mode where the unit changes brightness depending on the ambient light and turns off after 10 minutes of inactivity. Then is wakes up when it senses movement, and it doesn't take much. I have red dot sights on my handguns as well and I've always like them.
This sight has a 65 MOA ring that can be selected along with (or by itself) the red dot making it extremely easy to locate even in high stress situations. You won't be disappointed that you purchased this sight. Although you might have to eat beans and wieners for a few meals to pay the extra price. Do it. You'll be glad you did in the long run." — D. Howe

Get it from Amazon now: $372.65


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

"I saw a youtube video that was testing and rating this model. He did what he calls a bottle test on it towards the end which if it passed that..(and he really wanted it to because he so impressed by it) he would get one for himself. So he takes this water bottle that is full (16.9 fl. oz.) and just starts beating on the sight as hard as he can. He goes on for some time...maybe two minutes? It didn't give an inch and still held zero!! I never saw such a torture test as that one. And it really convinced me to buy it. IMHO it is better than my Eotech and I love the fact that it uses Solar to save battery and wakes up when moved. You must watch the video...guaranteed to impress you. Buy it!" — Rob in Sacto

Get it from Amazon now: $372.65


Holosun 510C - Reflex Red Dot Sight for Longer Barrels

"Glass Optical Quality/Characteristics
Holosun 510c: Excellent – Glass adds almost imperceptible blueish color. The coating on the glass nearly completely blocks red laser light.
EoTech XPS2-0: Excellent – Glass adds almost no color.
Trijicon MRO HD: Good – Has almost imperceptible magnification factor (probably around 1.05x). As noted by other reviewers, it is possible to sometimes see a reflection of the emitter/circuit board. This reflection is only visible under unusual/momentary lighting conditions. Neither the magnification nor occasional reflection bothered me.
Dot Quality/Characteristics
Holosun 510c: Excellent – nearly perfect line/dot quality. Very cool ability to switch between a single red dot and a red dot surrounded by a 68 MOA segmented circle.
EoTech XPS2-0: Good – but the center dot and the segmented circle is slightly fuzzy, like it is made up of a bunch of tiny, smudged pixels. Cannot switch to center red dot only.
Trijicon MRO HD: Excellent – nearly perfect line/dot quality. Very cool ability to switch between a single red dot and a red dot surrounded by a 68 MOA segmented circle.
Parallax
Holosun 510c: Very good – almost no/very little perceptible parallax.
EoTech XPS2-0: Excellent – almost no perceptible parallax.
Trijicon MRO HD: Very good – almost no/very little perceptible parallax.
Battery
Holosun 510c: Rated at 50,000 hours with one CR2032 for dot-only, 20,000 hours for dot + segmented circle. Also has “shake to wake” feature. Can be left “on” for years.
EoTech XPS2-0: Rated for ~500 hours with CRA123. Auto shutoff feature means that it may not be “on” if grabbed in the middle of the night.
Trijicon MRO HD: 2.5 Years of continuous use of dot; 75 days of continuous use for complex reticle.
Bulk/Field of View
Holosun 510c: Largest viewing window, with several milimeters of additional height over the XPS2-0. Thinner/smaller metal casing, resulting in near-perfect field of view. No visible battery compartment.
EoTech XPS2-0: Large viewing window. Slightly thicker casing than Holosun, but forward battery placement allows for otherwise unobstructed view (i.e. compared to Aimpoint PRO).
Trijicon MRO HD: Smaller tubular viewing window, but still easy to use with both eyes open. Slightly bulky control wheel on top (also holds battery).
Construction
Holosun 510c: Made in China. Overall seems well built. Quick Detach level is relatively thin metal and could break or bend if dropped while half-way open. Otherwise, seems like it could hold well through hundreds of QD cycles. LED emitter is not fully enclosed and could theoretically be damaged (but very unlikely as it is recessed).
EoTech XPS2-0: Made in USA. Seems very well built.
Trijicon MRO HD: Made in USA. Seems well built. Mount is not quick release and requires unusual keyed tool to attach/detach with screws." — CA Amazoner

Get it from Amazon now: $372.65

"Great holographic sight. I’ve used holosun products for a few years and beat them up and abused them and I’ve used aimpoints and eotechs and I will still buy this optic. It is rugged and it just works. Period. Battery life of an aimpoint with the sight picture of an eotech WITH a life time warranty. It really is inexpensive for what you get. 5 stars all day. You won’t be disappointed. Don’t buy an eotech. I love eotechs.. but don’t buy one over this optic." — Fletcher Valentine

Get it from Amazon now: $372.65

"Absolutely love this optic!! Out of the box you can tell it’s extremely high quality and well made fit and finish is perfect I can’t say anything bad. The reticle is super crisp wen with a 3x magnifier begins it and it gets super bright which I love and also get dim enough for Noght Vision use. If your on the fence hands down do it get this optic NOW, I think it’s better than an eotech for sure!! Hurry before they figure out they can charge double for this optic and up the price." — Keenan

Get it from Amazon now: $372.65

"I love this holosun red dot! You have 3 options, red dot, circle & circle dot. The brightness is easily adjustable with audible clicks when adjusting. Turns on and off in a breeze. The windage & elevation adjustments also have nice audible clicks ensuring that you are able to zero this optic flawlessly. If you are new to red dots or adjusting the zero on a red dot make sure you carefully read the directions so you can understand how to achieve the desired zero easily. Housing on this red dot is VERY strong and beautifully coated. The glass is amazing and the brightness is incredible as well. This thing mounts up SO EASILY! I own TRIJICON SRO’s amd RMR’s along with a few vortex optics and this is definitely up there quality wise with other $500-$700 optics. You will not regret this purchase. Get yourself one!" — Ryan

Get it from Amazon now: $372.65

"Initial impressions are very positive. The Holosun HS510C is like a micro version of the Leupold LCO (and that's a high compliment).
Sight picture is exactly what I wanted (once I turned off the big circle part): beautiful dot, sight window nice and wide, very natural to use with both eyes open, and barely any fairing/housing/knobs in the way around it. So easy to use with both eyes open, as it should be.
Add in that it's solar-powered and has auto off/on based on movement and yeah I'm all in. I can see myself replacing every micro dot I have with these. They're barely larger and I don't notice any increased weight over the micros.
I didn't know I needed a mini-LCO until I got this, sure glad I did!" — Tony Dravz

Get it from Amazon now: $372.65

"For an intermediate price point HOLOsun makes one of the best red dot optics with great features.
This one has a QD lever so it can but removed in a hurry. I appreciate the ability to choose between the 65 MOA circle, a red dot alone, or both together. The solar feature is awesome for saving battery life when shooting in daylight, and it regulates brightness to match conditions. One minor drawback is that if you are shooting from a covered area into brightly lit areas the reticle will be a little dim, but it can be switched to ON mode and have the brightness set to your favorite level. In ON mode it has a time out and shake awake feature, so you can leave it on all the time and it wakes up instantly when you pick up your gun. This feature works REALLY WELL, so you can trust it to be there when you need it, but not waste battery when you don’t.
I’ve used this in front of a standard height 3x magnifier on an AR and also on my 12 gauge shotgun with just the ring, because it is pretty close to the spread pattern of buckshot loads." — Chris Kilo

Get it from Amazon now: $372.65

"The packaging of this product is impressive, and then when you get it open the product itself is very nice. I love the auto on/off feature and the selectable reticle (circle/dot, dot, or just circle). The QD mount is solid and the entire product is well built. It is the perfect height for absolute co-witness with my Magpul flip up sights and was easy to zero. It takes the very common CR2032 battery (which I use in a lot of equipment) and if it does even 1/10th of the advertised battery life it will be so much better than any of my current red dots.
Update: Been using it for several months now. Had it on a 12 gauge shotgun, a 5.56 AR Pistol, Tavor SAR in 5.56, and it finally came to rest on my AR Pistol in 300blk. The auto on/off feature is great." — M. Shillingburg

Get it from Amazon now: $372.65

"I will never go to another DOT after using the Holosun 510C. I also have an Eotech XPS2 and I wish I would have purchased this before the Eotech. The image is much more crisp and smooth compared to the pixelated look of the Eotech. Don't get me wrong, the Eotech is a top notch sight, I just prefer this over the XPS2. The Holosun also has the ability for you the select from 3 different radicals on the fly. Also, what I really like is the wake feature. WHen you pick up your weapon, the optic automatically turns on. Will go to sleep as well after a set amount of time that you program. I own 2 of these and I bet I will get more in the future." — Unknown Soldier

Get it from Amazon now: $372.65