Holosun 507K X2

The 7K series Holosun reflex sights are a solid ultra compact pistol mountable optic option for slimline pistols and suitable concealed carry applications. If nothing else, they are at least worth considering.

The pistol mountable optic reviews have been abundant recently. However, I suspect this will be my last one for a good while. I can’t promise that, but that’s what I expect right now. Regardless, this time round I got my hands on a couple of Holosun 507K optics. A green one and a red one. I’ll refer to them from here on out as the 7K series or just the 7K. I get this might not be the common nomenclature used by most folks and I may very well be using incorrect or unaccepted nomenclature, but I think my reasons for calling them 7K will become apparent as we get into the review. With that said, let’s get started.

The Holosun 7K series optics are some of the smallest pistol mountable exposed emitter optics in the market today. The compact design appears to target the slimline compact pistols, such as the Glock 48 and the Sig P365, that are the current rage in the concealed pistol market. I use the word “appears” intentionally since I haven’t actually dug into the marketing materials or spoken to anyone at Holosun about the design intent, but the intention seems rather obvious to me. In fact, the first feature listed in the optic manual somewhat confirms this as it states “ultra compact size for concealed carry applications”.

As of writing, there are four variants of the 7K optics available in the market today. The 407K, available in either red or green, provides a 6 MOA dot aiming reference. The 507K, also available in either red or green, includes a 32 MOA ring in addition to a 2 MOA dot with a multi-reticle function. The multi-reticle function allows the aiming reference to use only the 2 MOA dot, only the 32 MOA ring, or both.

All of the variants include pretty much the same items as part of the package. The difference is the optic itself. The package includes:

  • A pretty basic plastic foam-lined box wrapped in a four sided paper-based sleeve,
  • a manual for the Holosun 7K series optic 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 essentially everything needed in order to mount this reflex sight to an optic ready slimline pistol with the exception of an optic mounting plate which is optional on some pistols.

Let’s take a look at the optic in detail. Starting at the front is the housing which is made from 7074-T6 and houses the lens and electronics. The window measures 0.58″ in height and 0.77″ inches in width. This is 0.05″ shorter and 0.14″ slimmer than the 7C series Holosun reflex sights many are familiar with. On the surface, the numbers might appear to imply there isn’t a significant difference between the view windows of the 7K and 7C series sights, but it is noticeable. That’s roughly 10% shorter and 20% slimmer. The view port isn’t so small that it’s not usable. I found the view port to be very functional. However, tracking the dot during recoil is quite a bit more difficult compared to the 7C series sights. Part of this has to do with the window size. Another part of this has to do with the snappier recoil characteristic of the smaller slimline pistols which in my experience tend to yield more muzzle rise to content with. It’s the trade off that’s made in exchange for the smaller footprints of these pistols which tend to be easier to conceal and more comfortable to carry.

Light transmission and edge to edge clarity through the multi-coated lens is very good. Considering the price point of the Holosun, I would say it’s surprisingly good. Even though the lens is supposed to have no magnification, or rather a 1x magnification, there is a tiny bit of magnification present which goes essentially unnoticed while shooting when the shooter maintains visual focus on the target.

Proceeding past the lens on the left hand side of the housing are the brightness and operation control buttons. The plus and minus labeled buttons allow the owner to cycle through a total of twelve (12) different bright settings. Ten (10) of the settings are intended for use in day light conditions and two (2) of the settings are compatible with night vision devices. The optic also supports two (2) modes of operation which can be managed with the same controls. Manual mode is the default operation mode which allows the shooter to increase or decrease the brightness using the plus and minus buttons respectively. Lockout mode, which is activated or deactivated by pressing and holding the plus button for three (3) seconds until the LED blinks once, locks in the selected brightness setting and prevents the brightness adjustments while this mode is active. Pressing and holding the minus button down for three (3) seconds will cycle through the different reticle options: ring plus dot, dot only, and ring only. Pressing and holding the plus button down for ten (10) seconds will enter sleep setting adjustment mode where the shooter can increase or decrease the sleep delay from ten minutes to one hour to twelve hours to disabled using the plus or minus buttons respectively. The LED will blink a specific number of times to confirm the selected sleep duration 1 blink indicates ten minutes, 2 blinks indicate one hour, 3 blinks indicate twelve hours, and 4 blinks indicate disabled. The sleep duration can then be saved by pressing both the plus and minus buttons simultaneously which also shuts down the optic and disables the “shake and wake” sensor. Pressing either of the plus or minus buttons when the optic is shut down will power up the optic and also restores all of the previous modes and settings in place and enables the “shake and wake” sensor.

The “shake and wake” sensor combined with the sleep delay duration are a couple of the features that help achieve the generous 50K hour potential battery life of the 7K series optics. Sleep only occurs when the optic is free of movement for the duration selected delay. The shake and wake sensor seems to be fast and effective as I’ve yet to experience an instance where I’ve picked up a powered on optic that was in sleep mode and the reticle wasn’t immediately present.

Opposite the control and operation buttons on the right side of the housing is the battery tray that holds a single CR1623 battery that powers the reflex sight. The tray is secured with a screw that can be removed and installed using a small flat head screwdriver.

Behind the tray, on the bottom of the housing in the center of the optic we come across the exposed LED emitter which reflects the 2 MOA dot and the 32 MOA ring off the lens making it visible to the shooter’s eye. As mentioned previously, the LED is available in either red or green. I often get asked by folks with astigmatism if green is better than red in terms of reducing the starburst some folks with astigmatism experience with reflex sights. The same folks also tend to inquire about whether or not the 32 MOA ring makes this sight more usable with their sight limitations. The truth is I don’t know. While I have astigmatism myself and I do perceive a slight distortion of the reflected dot and ring, I haven’t noticed any difference between colors or reticles in terms of function or reduced distortion.

I will say that I like the 32 MOA ring a whole lot. While some rifle shooters might be concerned that a 32 MOA ring as being too large to use for precise shooting like I was once upon a time, the 32 MOA ring caters well to fast and accurate enough pistol shooting applications under 25 yards. At 25 yards, the 32 MOA ring translates to an 8″ area of impact. That corresponds to the size of the typical body a-zone or high thoracic vital zone of a human sized target. At 12.5 yards, the 32 MOA ring translates to a 4″ area of impact. That corresponds to the size of a typical head a-zone or head box of a human sized target. At 6.25 yards, the 32 MOA ring translates to a 2″ area of impact. Since the 32 MOA ring is a rather large aiming reference, a pistol shooter can pick the ring and use it quickly on a variety of targets at common pistol target distances. When shorts require more precision, the shooter can use the center 2 MOA dot as an aiming reference. It’s due to these characteristics that I find the ring and dot reticle to be very functional and utilitarian for fast and accurate pistol shooting.

Moving past the exposed LED emitter we find the mounting screws which is followed by the windage and elevation adjustment dials found on the right side or top rear of the optic body respectively. The dials adjust in 1 MOA increments per click and have a total travel range of plus or minus 30 MOA. The clicks aren’t as tactile as I would like, but they are tactile nonetheless. The adjustment increments are inline with what I expect and find amongst pistol mountable optics.

The elevation dial is found between a shallow rear sight notch which can be used in conjunction with typical height factory mounted front sights as a back up iron sight solution. This is a pretty neat feature since the rear sight on some of the smaller slimline optic ready pistols is lost when the cover plate is removed in order to install the optic and there is no remaining real estate to install a rear sight.

A concern I had with this optic was whether or not it would be rugged and durable enough for concealed carry applications. While armed civilians aren’t as likely to get into a scuffle or bang the optic into other objects as a law enforcement agent is when pursuing a suspect, there remains a reasonable expectation that an optic should be durable and rugged enough to be relied on when the stakes are life or death. It took a little bit of searching, but I was happy to find that Aaron Cowan from Sage Dynamics has performed a 2000 round review of this optic which includes shoulder height drop tests every 500 rounds and the 7K series optic survived.

Overall, I like the 7K series optics a lot. I find them to be excellent well-priced optic options for slimline pistols and suitable for concealed carry applications. I currently prefer the 507K over the 407K variants due to the 32 MOA ring which I find lends itself to fast and accurate pistol shooting. I am very pleased with the optic and I’m happy with the decision to include it as part of my Glock 48 project.


Leave a Reply

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