Field test: new Sightmark Mini Shot M-Spec M2 Solar red dot on a Glock 21 Gen5 MOS in .45 ACP 

Two years ago, major spring trade shows saw the first demonstration models of the solar-powered variants of Sightmark's Mini Shot line. The Mini Shot M-Spec M2 Solar and M3 Solar models not only introduced photovoltaics to this product line, but are also Sightmark's only two fully enclosed pistol sights to date. Unlike conventional Mini Red Dot Sights (MRDS), which only have a lens open to the front and rear, the two new Sightmark optics have a housing that, in addition to the front lens, is closed off at the rear by a glass surface. In both cases, the front lens serves to project the red dot into the line on sight. However, a completely enclosed housing naturally provides better protection from dust and moisture for the LED that projects the dot and its electronics. The shooter usually has to pay for this advantage with a higher optic's weight and a higher price. While the first statement also applies to the Sightmark Mini Shot M-Spec M2 Solar, the second is only partially true here. But just take a look at our review to get an idea of the new M-Spec M2 Solar.

The Sightmark Mini Shot M-Spec M2 Solar reflex sight in detail

The new Sightmark Mini Shot M-Spec M2 Solar features a rugged, black anodized 6061-T6 aluminum housing and weighs 71 grams including the provided RMR-compatible steel base plate. Without this plate, the sight weighs just 53 g. In addition, Sightmark also supplies two clamp mounts with a Picatinny interface: one flat and one raised with a correspondingly large aperture, so that the latter allows co-witnessing. This means that  when mounted on the top rail of an AR or pistol caliber carbine, there is enough space under the sight to still be able to use the original open sights, for example if the red dot should refuse to do its job in a competition. Correct: although the M2 Solar is primarily designed as a handgun sight, there is nothing to prevent it from being used for short to medium ranges on a rifle, pistol caliber carbine or shotgun, especially in dynamic competitions. However, the base plate with the RMR footprint must be used as the interface to the sight for both Picatinny mounts. The M2 Solar itself is also attached to the base plate, which was previously screwed to the respective base using a clamp attachment. Clamping is via one fixed jaw and one movable clamp jaw, which is tightened by means of a Torx screw. Screws for attaching the base plate to the most common OR guns or adapter plates are included in the package, as well as the necessary Torx key and an offset screwdriver for adjusting the reflex sight. The manual, a battery and an optics cleaning cloth are also included. 

In the test, the Sightmark Mini Shot M-Spec M2 Solar had to prove itself on a Glock 21 Gen5 MOS with GECO 230-gr FMJ

The 3 MOA red dot is adjusted via two miniature turrets. The one for the elevation adjustment is located at the back on the top and the one for the windage adjustment is located at the back on the right side of the housing. The adjustment range is 110 MOA in elevation and 160 MOA in windage. The adjustment elements on our test sample do not have a click detent, but can be turned continuously. The adjustment screws are each marked with an arrow and the turrets each have a scale with 28 lines and another arrow indicating the direction of rotation "Up" and "R", respectively. The adjustment does not require much force. However, the resistance is always enough so that the adjustment can not change itself, even when firing.

During our test, the pistol still shot where we had shot it at the beginning of the test after several magazines had been fired. We used a Glock 21 Gen5 MOS, i.e. a pistol in .45 ACP, since this caliber is the maximum one that Sightmark recommends using the Mini Shot M-Spec M2 Solar with. The sight base plate was attached to the gun using the adapter plate 06 from the Glock MOS adapter set 02. Several boxes of GECO full metal jacket cartridges with 230-gr heavy bullets served as test ammunition. By the way, you will be able to read a detailed test report on the Glock 21 Gen5 MOS and other new Glock pistols here at all4shooters.com shortly.

Power is supplied by the solar panel when there is sufficient light, and otherwise by a 3-volt CR1620 button cell battery. This is a pure battery that can't be recharged. Thus, the Sight does not have a way to store the solar power. The battery compartment is located on the right side of the housing. Its screw cap closes watertight thanks to an O-ring. The housing of the enclosed reflex sight is waterproof in accordance with the IP67 protection class, which means that it can also be completely submerged under water for a time. According to the manufacturer, the battery lasts for about 20,000 hours in continuous operation at medium light intensity. Since the Sightmark Mini Shot M-Spec M2 Solar does not have an automatic shutoff or an on/off switch, the Red Dot is also constantly activated when the battery is inserted. Those who are too lazy to take the battery out after each use, however, will certainly not be afraid to spend 1 to 2 euros on a new battery for the sight every 2 and a quarter years – that's about the 20,000 hours that the button cell lasts according to Sightmark. 

Speaking of light intensity: the sight features automatic brightness adjustment. There is a tiny photo cell on the front of the optics above the front lens that serves as a sensor and adjusts the red dot almost optimally to the light conditions in the direction of the shot. In comparison, other sights that have solar cells usually use the solar panel to control the intensity of the dot. This is usually located on top of the housing. If most of the light falls on the panel from above – for example, when the sun is high in the sky or when there is artificial lighting at the shooting range – it can easily happen that the red dot is over-illuminated in front of the possibly darker target area. So Sightmark did well here to place the sensor on the front of the M2 Solar-Sight. 

Sightmark Mini Shot M-Spec M2 Solar specs and price

Our conclusion on the Sightmark Mini Shot M-Spec M2 Solar

The M-Spec M2 Solar adds a rugged and reliable model to the Mini Shot series from Sightmark. The completely enclosed reflex sight could fully impress during our test. Although the adjustment screws are designed in such a way that they do not adjust on their own and have an adjustment scale, we miss a click detent, which would simplify the adjustment, especially in difficult lighting conditions. On the other hand, Sightmark has really hit the mark by relocating the sensor of the automatic intensity control. This worked excellently in our test, the red dot always stood out from the target by just the right amount. The fact that the reflex sight has neither an automatic nor a manual shut-off device is easy to get over in view of the extremely long battery life of more than two years. Thanks to the solar panel, anyone who uses the sight exclusively in broad daylight on uncovered shooting ranges will probably not even notice that the battery is "already" empty. In view of the included accessories, the price of around 360 euros for this sight is also more than fair.

For more information on the new Mini Shot M-Spec M2 Solar reflex sight please visit the Sightmark European sales website.