Field test: the two Glock models 23 and 27 Gen 5 in .40 S&W with the new Holosun SCS-MOS-GR sight

When the term "OR" comes up, many shooters don't have to think twice. Red dot sights, which are fitted directly on the slide without any complex mount, are booming. Not only for sporting purposes, but also for hunting situations or self-defense.  Although not long in circulation, there are already signs of a significant improvement in this concept. With the SCS - MOS – GR Holosun offers a – no, not a “red dot” but a “green dot” sight. The abbreviation SCS stands for Solar Charging Sight, since it draws its power primarily from a photo-voltaic cell. Mounted on a Glock Gen 5 in .40 S&W caliber, the new product impressed us right away. But first things first: the Glock, which is a good 40 years old, has been on its fifth revision stage since 2017. The abbreviation "Gen 5" can be found on the guns. 

An old manufacturer's wisdom goes: the fewer changes are necessary to current models, the more successful the product itself is. Glock was well advised to change the successful Glock 17 model only very carefully and after longer periods of time. Many changes are hardly noticeable, even things that are essential to the gun, such as the increased outer diameter of the barrel in the 2nd generation, which required a wider slide hole. The larger slide stop is also not immediately obvious. In addition, it is not easy to see the changes incorporated without much fuss that accompany "official" generational changes. For example, during the life of the 2nd generation, changes were made to the firing pin, firing pin safety and extractor, among other things. Glock's 5th generation has two different ejector shapes. But a Glock remains a Glock, and that's good.

After five generations, the typical Glock silhouette is still clearly recognizable

The fully ambidextrous design of the Gen 5 is made possible by the double-sided slide stop. The fact that the magazine release button still has to be repositioned is more suitable for individual rather than pool guns; there is still room for modifications for the 6th generation. A significant change to the Gen 5 is the flared magwell and, in the case of the test gun – a Glock 23 in .40 S&W – the reduction of the trigger pull weight from around 2,800 to 2,600 grams. Long-time adepts among Glock users might be bothered by the increased clearance between the frame and the slide. However, the risk of malfunctions due to penetrating sand should only cause concern among military agencies. But all the changes between the first and fifth generation are not detrimental to the typical Glock silhouette. 

Glock 23 Gen 5 OR and Glock 27 Gen 5 specs and price

Our impressions from the test firing of the Glock 23 Gen 5 OR and Glock 27 Gen 5 with Holosun SCS-MOS-GR reflex sight 

The great evolution therefore takes place less through the gun than through the new Holosun sight. The unobstructed view of the iron sights means that they can still be used if the reflex sight fails. This was demonstrated by the shooting range visit. A positive side effect: if the illuminated dot is aligned with the front sight white dot, there is ideally no need for shooting in, depending on the load. In shooting, the superiority of a reflex sight to a rear/front sight set was demonstrated (again). However, it also showed the difference between different calibers of approximately the same power. This became clear during comparative shooting of a Glock 30 in .45 ACP. Its higher bullet weight at almost identical power (joules) "jerks" significantly more than bullets in .40 S&W.

Gen 5 Glock 23 and 27 OR test conclusion

Sporty users will cling to the 3rd Glock generation for the sake of accessory compatibility. Owners of a Glock Gen 4 MOS (Modular Optic System) are unlikely to be persuaded to change either by the magwells or the double-sided slide stop. However, anyone looking to purchase an OR polymer pistol should take a look at the combo presented here: a clear buy recommendation from the editors.