Holosun 507K X2 Pistol Red Dot [Hands-On Review]

SUMMARY

We tested the Holosun 507K X2 on some of our favorite 9mm handguns at the range and used this red dot extensively for concealed carry. For $260 (at the time of writing this), the Holosun 507K X2 offers three reticle options, great battery life & solid durability.

Holosun 507K X2 - Red Dot Pistol Sight

$260 at Primary Arms

The 507K X2 packs some great features into a compact size, and truly feels like some of the duty-grade competitors in the same class. In this review, we look at everything the Holosun 507K X2 has to offer and share our thoughts after firing thousands of rounds with it.

Pros and Cons of the Holosun 507K X2

Holosun 507K X2 Specs

• Reticle: 2 MOA dot, 32 MOA circle, or both
• Material: 7075-T6 aluminum housing
• Magnification: 1x
• Battery Type: CR1632
• Battery Life: Up to 50,000 hours
• Brightness Settings: 10 daylight and 2 night vision settings
• Mounting: RMSc footprint
• Water Resistance: IP67 (protected against immersion up to 1 meter)
• Dimensions: 1.6 x 0.98 x 0.95 inches
• Weight: 1 ounce (28 grams)
• Adjustment: 1 MOA per click, 30 MOA travel in both windage and elevation

Key Features of the Holosun 507K X2

Multiple Reticle System (MRS): The 507K X2 comes with Holosun's Multiple Reticle System, allowing you to switch between three reticle options:

• 2 MOA dot
• 32 MOA circle
• Combination of both (circle and dot)

The standard 2 MOA dot is great for more precise shooting. Even on most microcompact handguns, the 2 MOA dot will allow you to accurately push shots out to 50+ yards. 

The 32 MOA circle and 32 MOA circle + 2 MOA dot are easy to spot quickly, and are a perfect match for concealed carry (CCW) & self-defense applications.

As long as some part of the reticle is covering a larger target within 10 yards, you are guaranteed a hit which is great for high pressure situations.

The Holosun 507K X2 features 12 brightness settings and the two lowest settings are night vision compatible.

The 507K X2 does not automatically adjust its brightness based on surrounding light levels, but it does feature “+” and “-” buttons on the side which make it easy to adjust the brightness as needed. The two tactile buttons on the side of the optic are small but responsive, making adjustments easy even when wearing gloves.

Shake Awake & Battery: I’m really a big fan of the shake awake on the 507K X2. The sight automatically turns the optic off when it is not in use and immediately powers it on when it detects even the slightest motion. This can be turned off too, although I think the feature is super helpful for conserving battery life. Using this optic for concealed carry, it is also nice to know the shake awake has never failed in all of our testing with it. 

Holosun estimates the battery life to be about 50,000 hours on medium brightness, although I had to change the battery on mine after about 1 year of frequent use (about 4,000 - 5,000 hours–this might have been due to using a higher brightness setting). Even still, only having to change the battery once every year or two is still pretty impressive. 

Unlike the Trijicon RMRcc and Romeo Zero, when it does come time to change the battery the Holosun 507K X2 features a convenient side-loading battery tray allowing you to change the battery quickly without needing to remove the optic (and losing your zero). 

I noticed the optic was dead on the way to the range a few months ago. Using a small screwdriver I was able to quickly unscrew the battery tray and replace the battery, saving myself from having to re-zero when I got to the range which was nice.

Lightweight Design & Durability: The Holosun 507K X2 was created specifically for slim, subcompact, and microcompact handguns. Weighing in at just 1 ounce, this red dot sight has a super small profile making it a perfect fit for concealed carry & self defense pistols like the Sig P365, Springfield Hellcat, or Glock 43X MOS.

Even though the 507K X2 is lightweight and small in size, the sight was built with durability in mind. Holosun built the red dot’s housing with 7075 aluminum and ours has stood up well to bumps and drops at the range. We’ve had no issues with reliability, even during extended use and daily carry in the past year.

Going for bonus points, Holosun also packed an IP67 waterproof rating into the 507K X2, meaning it can withstand submersion in water up to one meter.

Hands-on Testing & Review

The Holosun 507K X2 really shines as a rugged red dot sight for subcompact/microcompact, self-defense, or concealed carry (CCW) pistols. I have been carrying this optic on my Sig Sauer P365 for the last year and the small form-factor of both the P365 and 507K X2 pair perfectly together.

Holosun 507K X2 for Concealed Carry

When looking for a concealed carry setup, I wanted something that was as small and lightweight as possible while still being performant. The 507K X2 fit perfectly in this role. I wanted to keep bulk to a minimum as I wanted to carry this setup daily without sacrificing comfort or additional weight.

I carried a Sig P365 with just the factory “X-Ray” iron sights–after adding the Holosun 507K X2 to the mix, I didn’t notice any change in weight or size which was great. The low profile of the red dot was a good fit for the microcompact pistol, and I could see other people loving this optic for daily carry.

The only issue I had carrying this optic was when a stray piece of lint got between the emitter and the glass at the range one time. I was still able to see the dot, but it was slightly blurred when looking through the glass. I was able to easily blow the debris out and the problem was fixed.

With open-emitter red dot sights, it is possible for lint or other debris to block the dot from being projected on the glass. I chalk this up to user error more than anything, as I let the sight (and my CCW pistol) get pretty dirty before cleaning it up.

I wouldn’t let this stop me from buying another 507K X2, but if this bothers you, Holosun does offer the EPS Carry red dot sight which is a similar size with a closed emitter. 

Shooting With the Holosun 507K X2

After firing thousands of rounds with the Holosun 507K X2, I got accustomed to the smaller window that comes with a red dot of this size. Before training with it, the dot could be hard to spot when drawing from a holster. With some practice, this became a non-issue.

The 507K X2 feels really sturdy, and I found myself using it to rack the slide when reloading. As far as shooting with this optic goes, the three reticle choices are really a nice touch. It is easy to change reticles by simply holding the “-” button for 3 seconds to cycle to the next option. 

I tend to keep mine on the typical 2 MOA dot–I like to have some fun at the range and practice shots at longer distances and the 2 MOA dot is great for more precise shooting at smaller targets. The 32 MOA circle and the circle + dot combination are great for close-range targets though, and are easy to spot through the glass.

The 12 different brightness settings are more than enough–shooting with the 507K X2 in low light (or bright daylight) is no problem at all. You can even turn the brightness down to lower settings to squeeze some extra precision out of the 2 MOA dot when needed.

After carrying this optic daily and shooting thousands of rounds with it, I would buy another one without hesitation if I had another pistol to mount it on.

Final Verdict

The Holosun 507K X2 is an excellent micro red dot sight that strikes a balance between affordability, performance, and durability. Its compact size makes it perfect for concealed carry, while features like the Multiple Reticle System (MRS), Shake Awake, and durable construction ensure that it's a reliable tool in both self-defense and competitive shooting scenarios.

While it has minor drawbacks like being an open-emitter and no automatic brightness adjustment, the overall value and performance of the 507K X2 far outweigh these issues.

For those looking for a high-quality, durable, and feature-rich optic for their microcompact handgun, the Holosun 507K X2 is an outstanding choice.