Holosun HS507C X2 with the ACSS Vulcan Reticle

Folks in the know agree the Holosun 507C is a fantastic pistol mountable dot. The same folks seem to be decisively split on the ACSS Vulcan reticle. They either hate it or love it. Let’s find out which bandwagon I’ll hop into.

The Holosun 507 series red dot sights have been around for a good while now and have a reputation of being a stellar exposed emitter red dot sight that rivals the Trijicon RMR, which has been heralded as the gold standard for quite some time, and is well suited for pistol use by several instructors I trust and other authoritative experts. Even so, my experience with the Holosun red dots has been limited to a handful of shots fired when friends have allowed me or asked me to check out theirs. That is, until now.

More readers than I can count ask me what my thoughts are about the Holosun 507 series red dot sights and I’ve parroted what I’ve heard from reputable sources with the caveat of not personally having any experience with them. A healthy number of those inquiries have been specific to the Holosun 507C equipped with the ACSS Vulcan reticle and to those inquiries I provided the same parroted answer with the an additional caveat of knowing absolutely nothing about the ACSS Vulcan reticle. Then a little over a month ago, I reached out to Primary Arms, who I’m affiliated with, and asked them if they would mind sending me a Holosun HS507C X2 with the ACSS Vulcan reticle to test and review. I figured the worst case scenario would be hearing a no. Much to my chagrin, Primary Arms obliged.

As soon as the dot arrived, I slapped it on the PSA Dagger and headed over to Bentley’s Firearms and Indoor Range to sight it in and send a few hundred rounds down range with it.

I considered splitting this review up into two posts. One focused on the Holosun 507 series optic and another focused on the reticle. This is similar to what I have done in the past, but I’ve decided against it, at least for this initial “first impressions” review. I may do things differently in follow up reviews, but for now I think it’s best to keep them together as my initial impressions on the hardware echo everything I’ve heard from trusted sources. As such, this should keep the dot portion of the review relatively brief.

So what does one get after spending roughly $320 on the ACSS Vulcan equipped Holosun 507C X2 red dot sight?

  • A pretty basic plastic foam-lined box wrapped in a four sided paper-based sleeve,
  • a manual for the ACSS Vulcan reticle,
  • a manual for the Holosun 507C X2 red dot sight manual,
  • a warranty registration card,
  • a lens cloth,
  • a pair of long Torx mounting screws,
  • a pair of short Torx mounting screws,
  • an installation and adjustment tool,
  • the red dot sight with a preinstalled CR1632 battery.

That’s pretty much everything anyone needs, short of an RMR footprint adapter plate, in order to mount this dot to a pistol and get started with it.

From front to rear, we start off with the housing which is made from 7075-T6 aluminum and houses the objective lens which measures roughly 0.63″ in height and 0.91″ in width. The window is a good size. It isn’t the biggest window, but it’s not the smallest. It feels comparable in size to the size of the Trijicon RMR window. Like most other exposed emitter red dot sights, the lens is multi-coated. Light transmission is great and edge to edge clarity is surprisingly clear and parallax free given the price point.

Right behind the lens on the top side of the housing we find a voltaic cell solar panel which powers the emitter when sufficient ambient lighting is available and helps deliver the spectacular 50,000 hour advertised battery life. The solar power feature seems to be a particularly important feature to many of the folks I’ve spoken to who have purchased this red dot. The common theme I find is that folks get a stronger peace of mind knowing that they are protected against battery induced red dot sight failures. While I find this feature interesting, I’ve witnessed one Holosun sight experience an electronic component failure which was not resolved by the solar panel nor a fresh battery. I’m not saying the solar panel isn’t valuable, but I am concerned that it is a feature which may downplay the importance of replacing the battery regularly for some folks.

On the right side of the housing (looking at the sight from the rear), we find the battery tray which allows the owner to change the CR1623 battery without dismounting the sight with a little assistance from a small flat head screwdriver.

Opposite the battery tray and on the right side of the housing we find the brightness and operation control buttons. The buttons allow the owner to cycle through twelve (12) different brightness settings, the lowest two (2) settings of which are night vision compatible. Additionally, the owner can use the buttons to switch between operation modes. By default the primary operation mode is “auto-mode”, which utilizes both solar and battery power sources to power the emitter. When the ambient light is sufficient, the reticle is powered by solar power and the brightness is automatically adjusted based on the solar power available. When the ambient light is low, the sight will revert to battery power where the brightness can be adjusted with the “+” and “-” buttons.

Pressing the “-” button for 3 seconds, puts the dot in “manual-mode”, which forces the optic to only use battery power and will prevent the optic from automatically adjusting the emitter brightness based on the solar power available. In this mode, the brightness can also be adjusted using the “+” or “-” control buttons.

Pressing the “-” button for 3 seconds again, puts the dot in “lockout-mode” which prevents additional brightness adjustments using the “+” or “-” buttons. An additional 3 second press of the “-” button cycles the operation back to “auto-mode”.

Regardless of the operation mode, the 507C sight will automatically activate sleep-mode after a certain period without movement unless sleep-mode is disabled. The time period is determined by the sleep-mode setting which can be changed using the brightness and operation controls. By default, sleep-mode is entered after 10 minutes of no moment. Pressing and holding the “+” button for 10 seconds will change the sleep time from 10 minutes to 1 hours. Pressing the “+” button again for ten seconds will change the sleep from 1 hour to 12 hours. Doing it again will change the time from 12 hours to disabled. One more time and we are back to a 10 minute delay. The dot’s “shake-awake” sensor brings the sight out of sleep-mode at the instant movement is detected. I suspect this feature is one of the reasons the marketed battery life for this dot is 50,000 hours. As of writing this, I don’t know what the battery life is when sleep-mode is disabled and the highest brightness setting is locked in. At the same time, I see this configuration as being atypical, but it is something to be aware of as a problem if the dot is going through batteries like a new-born goes through diapers.

Continuing towards the rear we find the exposed reticle emitter which projects the ACSS reticle onto the objective lens. I don’t have much more to say about the emitter itself and I will cover the reticle after we finish the front to rear walkthrough.

Behind the emitter and back on the right side of the optic we find the windage adjustment dial. A bit further behind the windage adjustment dial and back on the top side of the optic, we find the elevation adjustment dial. Both dials are adjustable using a small flat head screwdriver and provide exceptional tactile feedback where each click represents a one (1) minute of angle adjustment. After zeroing, the dot held zero without any problem while I sent a few hundred rounds downrange.

Before getting into the ACSS Vulcan reticle, which I’m now thinking might be better reviewed in its own blog post, I want to add that the durability of the Holosun given its price range is exceptional. I don’t say this lightly, but I am basing it on what I have gathered from trusted feedback and the findings from Sage Dynamics which are documented in their MRDS white paper. Combining hearsay and research with my own first hand experience, I find the Holosun 507C series red dot sights to be a great choice for folks who are looking for a value-priced pistol-mounted red dot sight for recreational, defensive carry, or competitive use cases. Are there better for each of those use cases? Yes, absolutely. Are there more affordable options? Yes, but none that I can think of that would be better at the same price point or lower for those use cases. This opinion holds true even when the Holosun sight isn’t equipped with the ACSS Vulcan reticle.

Okay. Let’s talk about the reticle. I promise, I’ll do my best to keep it brief, which is a tall order and will likely result in a follow up post that will dive deeper into it. But alas, let’s give it a try.

The reticle consists of two parts. The first is a 10 MOA tall chevron found at the center which is, in the most elementary sense, what is used for aiming purposes. The chevron is enclosed in a 250 MOA circle. The chevron is designed to work with several different handgun and rifle cartridges and provide bullet drop compensation at various distances assuming it is zeroed with those cartridges as intended. To be completely transparent, I’ve only worked with this reticle using 9mm handgun cartridges and didn’t follow the zero specifications set forth in the manual. As such, I will not provide any opinions regarding the chevron’s bullet drop compensation features.

I suspect several readers are curious as to why I didn’t follow the zero instructions and some might feel short changed after reading this far into the review. The truth is that I tend to stick with 10 yard zeros for pistol mounted dots based on my ability to zero pistol mounted dots. Additionally, I don’t do much with pistols beyond 25 yards given I rarely exceed those distances in pistol competitions and distanced beyond that are anomalous to self defense situations. I’m not saying there is no value in shooting pistols beyond 25 yards. Rather I’m saying that my skill level limits my ability to zero a pistol mounted red dot effectively beyond 10 yards and affects what I can effectively test beyond 25 yards.

That said, I zeroed the tip of the chevron to 10 yards with the 9mm Dagger. When shooting static targets without time pressure, I found the chevron easy to pick up and exceptionally easy to aim with while applying hold overs between 3 to 25 yards to make slow precise hits. Under time pressure, I found the easy to pick up 10 moa chevron to be fantastic for making good enough hits quickly at close distances and I found it trivial to see a much finer grained aiming reference for precise shooting under the same pressure. As I did my testing, the question that kept creeping into my mind was “am I doing anything here with the chevron that I can’t do with a traditional dot?” The answer to that has continued to be “not really” so far.

“Not really” isn’t as definitive as a hard no. Let me explain. I did find the 10 moa tall chevron significantly faster to pick up. Under time pressure, I was able to use the large chevron to make very fast hits using a coarse sight picture. While I don’t have split time data to back up that subjective perception, the feeling of making coarse grained hits faster than I normally do using the 2.5 to 3.25 moa dots I’m most familiar with was very prevalent.

At the same time, I found myself getting “sucked into chevron” much more often than I find myself getting “sucked into the dot” with other pistol mounted optics. Again, I don’t have empirical data to support this subjective feeling. Nevertheless, I had to make a more concerted effort to remain target focused while using the Vulcan reticle than I typically do with a traditional dot. Lowering the brightness on the chevron helped with this, just like it seems to with traditional dots, but I still seemed to struggle more with remaining target focused when using the ACSS Vulcan.

I found the enclosing 250 moa circle to be immensely helpful in aiding me to find the chevron when it was immediately visible after I fumbled a draw or a grip. This was a rare occurrence for me during my testing, but finding the dot is something that I see a lot of folks new to pistol mounted red dot sights struggle with and it was something I struggled with myself. As such, I found this feature to be a remarkably useful training aid. On the other hand, I suspect it might be misused as a crutch by newer dot users which may curtail their presentation development to minimize their dependence on this feature. In my honest opinion, the usage of the enclosing circle should be the exception rather than the rule. Thankfully, the enclosing circle can be disabled by pressing and holding the “-” brightness control button for ten (10) seconds which can help force better presentation development while training and practicing.

Overall, I see the reticle as a double edged sword. On one hand, the large chevron can be strikingly useful for fast coarse grained shooting and the enclosing circle can be extraordinarily handy for aiming and presentation corrections. On the other hand, the large chevron can hinder a shooter’s ability to remain target focused and the enclosing circle may hamper the development of presenting a pistol with a mounted red dot sight. When the reticle is exploited for its benefits, it is absolutely amazing.

So what is my verdict?

In summary, the Holosun 507C series red dot sight is a go for pistol mounted use. While I see some potential drawbacks to the ACSS Vulcan reticle, I think the good outweighs the bad by a long shot and I like it a lot. As such, I’m going to say it’s a go. Sure, it may require more deliberate effort to remain target focused and might be misused as a crutch. However, the benefits of large aiming reference for dynamic shooting under pressure in addition to the training aid the enclosing circle provides make it an extremely attractive and valuable proposition.


Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.