Although the Californian company Holosun was founded only seven years ago, it's already internationally recognized as a well-established player in the field of reflex sights. Holosun offers single-lens, open-housing optics as well as fully closed reflex sights – this is the case with the present optic. At just over 300 euro, the HE503GU-GR Elite model with the "Made in China" label is in the medium-price range for reflex sights. This is not only true for similar optics from other manufacturers, but also for in-house sights: a 530 series Holosun, for example, costs about twice as much as the 503 presented here, but the more expensive 530 series with a 30 mm front lens also comes with extras such as a titanium housing, a particularly well-protected reticle adjustment mechanism, honeycomb filter, quick release mount and the like. In shape, dimensions and weight, the optics reminds a little bit of the Micro series from Aimpoint..
The Holosun HE503GU-GR Elite in detail
In the present version, however, the 2-MOA dot does not glow red, but green. In addition, the user has the option of switching between a pure dot and a reticle with a dot within a 65-MOA circle at the push of a button. This target picture is strongly reminiscent of the reticles from EoTech. A battery should supply the Holosun with sufficient power for up to 20,000 hours, and even up to 50,000 hours with a pure dot reticle. This long operational readiness is also helped by an additional function which the manufacturer calls "Shake Awake": if the Holosun is exposed to even the slightest movement or vibration, the reticle automatically activates in the last brightness level set. After a few minutes of complete motionlessness, it automatically switches off again. There aren't many controls on the compact optic. Two push buttons are used for manual on/off. They also regulate the two reticle formats and the 12 brightness levels, whereby the weakest settings should also be suitable for night vision devices. The inverted protective caps serve as a tool for reticle adjustment. Adjustment is made in 0.5 MOA (angular minutes) per click, the elevation and windage travel range being plus/minus 50 MOA. The 503GU-GR Elite is factory equipped with two mounts for Picatinny rails. The version with a high AR mount offers the right height for co-wittnessing with the mechanical sights in the lower third of the lens. Alternatively, the Holosun 503 can be mounted with the second mount a good 0.94"/24 mm lower on a Picatinny rail.
Holosun HE503GU-GR Elite - Our impression
There was nothing to complain about fit and finish. The mounting system, however, turned out to be quite simple: a 10 mm long clamping jaw can be tightened via a Torx screw that can be reached from the side. The body of the screw then sits between two Picatinny teeth and is also the only counter bearing of the assembly. This was solved in a more complex way, for example, when assembling the Holosun 530 series. Besides the quick-release lever, there are two additional assembly crossbars as counter bearings.
For the shooting range visit, the testers mounted the reflex sight on a 9mm semi-automatic rifle from Troy Industries. Shooting was quick and easy, as the rifle got along very well with the sight factory zero and the elevation and windage click-stops could be felt and (with unprotected ears) heard well. Color fidelity of the optics can't be criticized, the two available reticles were sharp and the maximum brightness levels were sufficient for a clear green reticle even in sunshine on a bright background. The automatic on/off function worked perfectly every time. In addition, the test optics were pleasantly sensitive: depending on the ground and the stability of the rack, it may be sufficient to stand close to the gun in order to reactivate the illuminated dot.
Holosun HE503GU-GR Elite wrap-up
With the HE503GU-GR Elite, Holosun offers a compact, well-equipped reflex sight that revealed no optical or mechanical flaws in the test – a good choice for sports use or for hunting in motion. The two selectable reticles offer a reasonable additional option compared to a single dot reticle and with regard to features, the "Shake Awake" automatic system in particular made a practical and reliable impression.