Holosun Paralow HS503G Red Dot Sight - ACSS CQB Reticle

Manufactured by Holosun
Manufactured by Holosun
51 Reviews

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Exclusive to PrimaryArms.com and Primary Arms authorized dealers.

Primary Arms and Holosun have combined forces to bring you the power of the patent pending ACSS® CQB reticle in a red dot sight for the first time! The problem with dot sights is that a large dot is great up close but less useful at distances beyond 100 yards, because the dot becomes too large to aim with precision. A small dot used in conjunction with a magnifier fixes that problem, but is slower to acquire in close range snap shooting. The ACSS reticle uses a large chevron that the eye picks up very easily for up close shooting. At longer distances, the tip of the chevron is an infinitely small aiming point perfect for taking precise shots.
Using "zero" ranges of 25, 50, or 100 yards, the ACSS BDC is compatible with the following calibers:
  • 5.56 NATO / 5.45x39 from 100 to 600 yards
  • 300 BLK / 7.62x39 from 50 to 450 yards
  • 12 gauge 1 oz. slug from 25 to 150 yards
  • 7.62x54R from 100 to 600 yards
  • 7.62 NATO / .308 Win from 100 to 600 yards
  • 300 BLK 220 gr subsonic from 50 to 150 yards
  • .22LR 40 gr from 50 to 175 yards
  • 9mm carbine 115gr from 25 to 200 yards

The ACSS features three BDC dots underneath the chevron, allowing an unprecedented 600 yards of bullet drop compensation in 7.62 NATO or 5.56 NATO calibers. Auto ranging and wind leads are also incorporated into this smart reticle. A CQB horseshoe grabs the eye instantly for close quarters shooting and also approximates the spread pattern of 00 buckshot at 25 yards. The reticle for this sight is a central 2 MOA dot, centered in a 65 MOA circle with four positioning points. The diameter of the circle reticle represents approximately 5'5" at 100 yards 170cm at 100m.

The HS503G is a proven micro dot sight with an auto-on function that switches on the power with a slight movement of the sight. It comes with a 1913 Picatinny base which is removable, revealing an Aimpoint Micro-compatible base underneath. It also comes with the lower 1/3rd co-witness riser mount shown in the photos.
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Battery TypeCR2032 3V Lithium Coin
Brightness10 Settings
Click Value1/2 MOA
FinishHardcoat Anodized
MaterialAluminum - 6061-T6
Night Vision CompatibleNight Vision Compatible
ReticleExclusive ACSS CQB
Reticle ColorRed
Warrantylimited lifetime
Weight4.87 Oz
  • HS503G-ACSS overview with Dimitri Mikroulis
  • HS503G Red Dot ACSS by SuperSetCA
  • ACSS CQB micro explained by Dimitri Mikroulis
  • Holosun 503G Review by MrGunsNGear
  • Holosun ACSS Red Dot Review by Sootch00
  • CountryMash pushes the Holosun ACSS to 500 yards

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see www.p65warnings.ca.gov

BDC works as advertised


I mounted and zeroed at 100. Immediately moved to the 400 yd target and used the BDC. Right on target!! Awesome product.



FINALLY! After years of research and debate between variable powered optics (1-4x/1-6x) and red dots/holographic sights (aimpoint, eotech, meprolite, etc.) I am proud to say that this one takes the cake with ALL the bells and whistles at half the cost!! Simple, sleek, and durable. Not to mention battery life! We are in the golden age of optics and this one is hard to beat. GET ONE!
<br>Experience with Primary Arms customer service:
<br>After asking to replace the first optic that I had purchased due to a questionable defect Primary Arms was quick to help me at every step of the way in trying to identify the source of the problem and was even quicker at replacing the optic. They even included a sticker! Hahhah why not? Long story short is that the quality control had been tightened up without question and I am still stoked about this optic and its incredible quality both with its construction and the sharpness of the glass and AMAZING reticle. THANK YOU PRIMARY ARMS!!!!!!

HS503G - Watch all the videos, buy the sight, have fun!


I am fairly new to red dots. I had to go through the learning curve. I bought really cheap just see what all the fuss was about. I watched Youtube videos made by everyone. After a lot of research I finally purchased two of these. The need is there and I have a tactical shotgun that would benefit as well. I'm not after 500yrd targets, but this has made that an option to train on (I have a 1Kyd range near by). What I like best about this, so far is the quick and accurate target acquisition. I received this this weekend. After it was zero'd I just had fun. Pull up off the bench, general resting position to shooting a target was like cheating! Next purchase will be the 3x LER Gen IV is next.

A must have for any medium/short range rifle.


The holdovers work great! Rang a 12" gong at 400 yards consistently. And the auto off/on is great for range days and drill practice where youll be setting the firearm down a lot.
<br>For the price you cant beat it. It's a fraction of the price of all the popular name brand rds' and has so many more features.

I Took a Chance

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Fantastic red dot. I have had ssues with some red dots over the years because of my astigmatism, and have gotten some prism scopes as a result.<br><br>I took a chance on this one hoping that the reticle design might make a difference, and I'm glad I did. This reticle design seems to have less of a negative effect with my astigmatism and I'm thrilled with this optic. Obviously, everyone's eyes are different, so YMMV.

Think I was sent a demo unit!


I just received my HS503G ACSS And have to say, I'm a little disappointed. It seems I was sent a used unit or a demo. Battery already installed in the scope, scratch on battery cover and little dusty and smudged. I'm hopefull I didn't buy a returned unit.
<br>From PA: There shouldn't have been a return in general circulation, but we want you to be 100% happy. Contact us so we can swap it out.

Chevron not clear at all


Just received the dot for Christmas. I had high hopes for the chevron reticle , and was very disappointed. I cannot see the chevron sight at all . Looks like a dot . Even my son , with much better eyes can't see it . Don't know if I got a bad unit or what . Other than that , it seems well made .

Overall . Great optic


Was disappointed when I first got it
<br> Chevron wasn't clear at all . Must have been the lighting indoors . Put it on and took it out to zero it and the reticle was clear , although a lot smaller than I thought it'd be . Think I'm going to get the magnifier , just not sure which one . Overall , I really like it . Was only able to take it out to 75 yards , but it's a great red dot for the money

This is the future of red dot sights.

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I love this sight so much I've bought THREE of them. The ACSS reticle is an absolutely brilliant idea. It's like a chevron Acog with true 1x magnification. The chevron tip is so crisp and sharp that it feels like the limit of precision is only up to your eyes or magnifier, not the sight itself -- unlike every other red dot or holo sight on the market, where the large dot gets in the way of precise shooting.<br><br>To give you an idea, I've used in the past: EOTech, Aimpoint, Meprolight RDS Pro, Trijicon MRO, etc. This optic is better than ALL of them in terms of the reticle. The only thing I'm not 100% confident about yet is durability until I stress test them personally (which takes a long time).<br><br>And the cherry on top? It's cheaper than all the other military grade optics. Time will tell if it holds up, but there is certainly nothing lacking in fit and finish vs for example an Aimpoint T2.

Mount Recommendation


I've taken it to work and absolutely loving the optic. The mount, though, came loose relatively quickly. I'm wondering what mounts people would recommend to keep the optic at the exact same height (in order to be able to continue to use my 3x magnifier).
<br>Once I resolve the mount issue, this optic is definitely coming with me on my next deployment.

Fantastic Product. Fun to Shoot With.


I'll keep it short. Great product. Put it along side a Primary Arms 3x magnifier and I couldn't be happier. Easy to use and accurate. Haven't had any issues with it.

16" 308 barrel


I mounted this red dot on a DPMS Gen 2 Recon. I zeroed as instructed, 1 inch high @ 100 yards for a 308. I ran a biathlon with this set up and it came through like a champ! 300, 400, 500 yard shots were a breeze using the appropriate dots. The chevron handled everything closer. I absolutely love this red dot!


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Was a little wary after other red dot experiences. After a couple of range days this red dot is my new best friend. Plenty of adjustment for bright or dim days. BDC is absolutely dead on at extended ranges. I will be buying a couple more of these without a doubt. Great to see a product that delivers as advertised. Great job Holosun and Primary Arms!!!!

Looks good so far!


After some research on red dots and the like I bought two of these when they came in stock. Unlike many people I'm not using an AR at least one is going on an FAL. The higher mount will allow use of irons underneath fairly well if its mounted close to the rear sight. I liked the lower mount as its closer to bore axis. The reticle looked too small at first but once I mounted it on a rifle it was much better. I have not zeroed it yet so it still remains to be proven with repeated 308 recoil. I'm an iron sight rifleman but at some point our eyes stop working as easy and this sight seems to be just the ticket: a fine illuminated aiming point with calibrated aiming points for the distances I can actually SEE. The motion activation Is a good feature. I do have to admit I distrust electronics and technologically advanced gear as I expect it to fail when truly needed. But i'll give this sight a good evaluation and see how it does.

Great product and great customer service by Primary Arms as usual!


Received this red dot earlier this week and took it out to the range today. After shooting about 300 rounds I can say that I like this sight a lot. The ACSS reticle and the glass itself are crisp and clear. For the money spent I am definitely pleased. Beyond that I received it within 3 days of placing my order. A+ for PA!

Get it.


Was having a lot of trouble deciding whether I wanted this or the 1-6x. I love how quick a red dot is. I wanted the distance of a scope. While a scope is better served trading long shots this particular red dot with a magnifier is actually a worthy competitor. That would be a ridiculous thing to say with any other red dot. This one will obviously not be as ideal when taking a long shot but imagine having the reasonable ability to do so but then have ask the advantages and more of a red dot. The reticle is freaking sweet. With the circle dot it is very fast acquisition close range. At long ranges the chevron is awesome at finding that pin point you want to shoot to. Next thing. On a second focal plane scope the reticle is only really accurate on its last setting. So all the other power settings you have to toggle through to get to it are fine and all...but personally I'd rather just slap my magnifier over this red dot and be there immediately. I have the primary arms 3x ler. I plan on getting the 6x on a quick detach just for kicks. I'm loving the red dot. Get whatever you want...the 1-6x is still in my future but for now I got third and am glad I did. Get one of the two...heck get both. No regrets.



unbelievable for that price. got to test it out at the range today and it works flawlessly. i had ordered the hs403b and returned it because the dot was not sharp and it was distracting and the battery tray was sub par. this fixed all of those. reticle is tack sharp even in bright daylight with brightness all the way up. battery know is on the side under a screw cap and build is very robust for the price. other than reliability of the name it makes me wonder why other sights are so much more expensive.

Good to go


In my honest opinion which isn't an expert one for the price you can't beat this little red dot. It's packed with features and does its job what more can you ask for. Consistently hitting a 6 inch paper at 100 yards with my Tavorx95. Its also built very solid in my opinion it doesn't feel or look cheaply made like a lot of others in this value price range. I'm probably ordering another Holosun dot here in the near future and the customer service at Primary Arms is top notch.

Mount broke after two shots

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So far the site works great. Fit and finish on par with my T1 and T2. The red dots crispness is as good if not better than the T2 (which is improved over the T1) and much better than the eotech that this sight is replacing. If it proves to be as durable as the aimpoint then it will be a great sight for years to come.
<br>Now the one big negative ......the mount. It looks great, fits great, but broke after two shots on a 300BLkout. Took two sight in shots, then reached up to remove the elevation cap and the sight fell off the gun into my hand. The screw broke off half way thru the threads in the base of the mount. I used and FAT wrench to torque it to about 20-25in/lbs and used blu 242 thread locker on install. SO needless to say I am extremely disappointed in the mount. Do yourself a favor and order a LaRue, Midwest or American Defense mount when you order this sight and you won't waste a trip to the range.
<br>5 stars for the red dot and 1 star for the mount.


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Couldn't be happier very nice optic nice features love the chevron priced just right... have a PA 6X Magnifier with QD mount sighted in at 100yds 1/2 moa grouping. Touchin 2in plates at 200yds in no time . Primary Arms customer service is amazing will be coming back !

Update to earlier post - 11/15/2016 4:25 pm


Bought two of these Sights
<br>1. Put one on a DP-12 shotgun. The ring and chevron are perfect for this weapon. Groups of 1" @ 25ys (slugs).
<br>2. 2nd sight is on a .300 BO pistol. I did add the following :
<br>--Primary Arms Advanced 3X Long Eye Relief Magnifier, Black PA3XLER-AD. It is functional as close as 15ft. 100yds is unbelievably clear! I'm not a great shot, but my normal group at 50- 1/2", and 100- 1.5".
<br>--Primary Arms Quick Detachable Flip To Side Mounts - Standard Height, Black PAQDMQF-01. This is NOT "slap to the side" mount, but I don't need that. It is "move to the side" and that works for me.

Sold my MROs and Aimpoints


While this is a budget friendly optic, the build quality is exceptional for the price point. I beat up my optics by throwing them in my bags, accidently dropping my firearms, tossing multiple firearms and items in my bags. I travel to and from indoor and outdoor ranges in temperatures ranging from 10f to 105f and not once during my year of ownership has my original 50/200 zero strayed or been lost on any of my Holosun optics. In my year of ownership, I have not yet needed to change my battery.
<br>The lens objective is 20mm. The glass is clear with little to no blue/green tint and handles sun glare extremely well during my bright outdoor shooting adventures. The reticle brightness even goes plenty bright to shoot outdoors in the bright sun during any time of the day. I seriously have no complaints on how it handles the sun. Both (to my eyes) seem to be a true 1x for magnification.
<br>Seriously, I'm a huge fan of Holosun and sold my Trijicon MROs and Aimpoint's for these.

Exceeded my Expectations

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Pros<br>- Stands up to hard abuse.<br>- Horseshoe makes a night and day difference for CQB target acquisition<br>- Looks great through Night Vision<br>- Works great for 5.56 and .308. Works even better for .300 BO<br>Cons<br>-Slight orange glare if the sun hits it just right while a witch is performing a spell to try and through you off your game<br><br>If you're thinking about spending money on an Aimpoint, Trijicon, or Eotech, then don't. You're reading this review because you're having second thoughts about spending that much money on an optic, so buy this Holosun instead. The glass and reticle are incredibly clear. The horseshoe does a better job for CQB than Eotech, the ACSS reticle does as good of a job as a Trijiconfor reaching out, and the battery life is on par with an aimpoint. If you're worried about ruggedness, then don't. This sight has been run through the gauntlet and the dings and dents I have put in it have not caused it to lose zero once or not turn on.

Buy it!!! You will be totally satisfied!!!

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Wow!! Simply awesome. Hard to believe the couple of poor reviews. Mine is much better that what I expected for $220. I'm sure there are a few bad ones but Primary Arms will fix that in a hurry so its hard to believe.

Initial issues


Initially very excited about this optic. Clarity was great and more crisp than other red dots I own. However with only 200 rounds of 556 something must have shaken a circuit loose in the optic because it is no longer functioning. A battery change did not fix the problem. Sent it back to PA hoping I just got a dud unit. Hopefully a more positive review will follow with the replacement unit.