REVIEW: Holosun HS503R Red Dot

HOLOSUN has long established itself as a manufacturer of high-quality Red Dots in the market. The housings and functions have been continuously developed and customer feedback has been consistently listened to. Customers wanted a compact, enclosed Red Dot with an adjustment knob. So, the HS503R was created, and we took a closer look at it.

This is how you receive the HS503R. With the 503 series, it is possible to switch between reticles, as is the case here.

The "R" in the name HS503R stands for Rheostatic, and it features a rheostat adjustment knob for adjusting brightness settings. This means a knob with noticeable clicks. Such rotary switches are already known from other reputable manufacturers. We like them.

This is everything you get in the package. The HS503R, two mounts (one high, one low), a Torx wrench, cleaning cloth, and a battery. Everything you need is included, the rubber cover is also there, but unfortunately absent for the photo shoot.

The two included mounts are 6mm and 24mm high, measured from the top of the rail to the highest point of the mount. This positions the optical axis of the sight 25.4mm and 43.4mm above the top of the rail. Speaking for all AR-15 enthusiasts: in absolute co-witness or lower 1/3 co-witness.

Like most optics from HOLOSUN, the HS503R features the mounting pattern of the Aimpoint MicroT1, making it compatible with various third-party mounts.

We tested this and it fits perfectly. Here is the HS203R on the very high mount from Unity Tactical - HERE in the SPARTANAT Review.

As mentioned, there are two different reticles available. One is the 65MOA circle reticle with a 2MOA dot in the center. Some will be reminded of the classic EOTech reticle. The circle is clearly visible, as it should be.

If you turn the adjustment knob beyond the twelfth brightness level, the reticle will switch. Simple yet effective.

The second reticle is just the 2MOA dot alone. In this mode, the HS503R is identical to the HS403R, which only has the dot as the reticle.

To hit something, the HS503R naturally needs to be adjusted. This is done using the adjustment screws, as usual. The protective cover serves as a turning aid and also indicates the direction for you.

UP/R stands for point of impact shift. So, if you turn counterclockwise in terms of height, the reticle shifts down (!) and the point of impact shifts up. We admit, we always initially turn in the wrong direction.

The reticle is clearly visible, the view through the HS503R is impeccable, and according to IP67, it is also waterproof. We initially had a small issue with what seemed like a loose connection while shooting, but the battery cover was simply slightly loose. Once tightened properly, we had no issues. That's how it should be.

Technical Data

• Dimensions: 39x65x40 mm
• Material: Aluminum
• Housing color: black
• Weight: 106 g
• IP protection class: IP67
• Operating temperature: -30°C - 60 °C
• Storage temperature: -40°C - 70 °C
• Reticle type: 2MOA Red Dot/65 MOA Ring
• Style: Micro
• Lens size: 20 mm
• Magnification: 1x
• Solar cell: no
• Automatic brightness adjustment: no
• Shake Awake function: no
• Memory last setting: no
• Battery life: 50,000 h
• W&E scale: ±50 MOA
• Vibration resistance: 1000 G
• Flip cap type: no
• Killflash: no
• Light sources: LED
• Reticle color: red
• Operating voltage: 3 V DC
• Battery CR2032
• Battery compartment: Side

Whether on an AUG, an AR-15, or an AKM, the HOLOSUN HS503R has always worked flawlessly and held the adjustment problem-free.

CONCLUSION: The HS503R does what customers have asked for and all at an unbeatable price-performance ratio. Thanks to Micro T1 compatibility, you have a variety of mounts available, with the included ones covering 99% of cases without any problems. A truly great alternative for all shooters who value quality as well as price.

The HOLOSUN HS503R is available at Holosun.eu for 309.90 Euro.

HOLOSUN on the internet: www.holosun.eu

LASERLUCHS on the internet: www.laserluchs.de