SIG Sauer Electro Optics: Tango4 and Tango6 riflescopes in a practical test

The two SIG Sauer Tango riflescopes are designed primarily for tactical use and sporting long-range shooting. Common design features that distinguish them are: sufficient maximum magnification, a reticle mounted in the first image plane (which keeps the reticle dimensions the same at any magnification), reticle illumination that illuminates all reticle markings, parallax compensation, and easy-to-grip controls.

The smaller SIG Sauer Tango4 riflescope
The smaller SIG Sauer Tango4 riflescope with mounted sunshade.

SIG Sauer Electro Optics Tango4 riflescope

This rugged 30-mm main tube diameter scope in the 1,000-euro price range has a surprising amount of features to offer considering its low price, and its 24x maximum magnification makes it suitable for many sporting endeavors. The "Dev-L" reticle provides a lot of information with the Mrad or MIL markings. Besides the common 0.5 and 1 Mrad hash marks (= 5 and 10 cm at 100 meters), we find 0.2 Mrad marks in the vertical line below the center dot. If there is no time to operate the elevation adjustment turret when shooting at long range, for example at 500 meters, these marks, which equal to 10 cm at that distance, give you a more accurate aiming point than if you had to make do with 0.5-degree hash marks. We personally liked the "Dev-L" reticle because it provides a lot of information at high magnification without obscuring much target area. On the other hand, the reticle is still usable at low magnification because the thicker bars carry the thin lines of the center and guide the eye to the target. The manufacturer's stated overall elevation adjustment range of 17 Mrad/170 cm is a bit meager for a long-range scope, though we measured 179 centimeters ourselves on our test scope. With a neutral mount, half of the adjustment circumference is below and the other half above the reticle center. This gives you 85 clicks (1 cm/100 m or 0.1 Mrad) in elevation, which is too close for distances in the 1,000-yard (914-m) range, depending on the caliber. This is absolutely okay for the price range, but then you need an additional scope mount with integrated forward tilt for longer distances.

SIG Sauer Tango6 cockpit
SIG Sauer Tango6 cockpit: the elevation and windage adjustment turrets must be pulled out of the lock for adjustments. The left turret has several functions: in addition to parallax compensation and reticle illumination, the battery cover labeled "LevelPlex" is effectively a push button for activating and adjusting the anti-cant system.

SIG Sauer Electro Optics Tango6 riflescope

The high-performance Tango6 with a 34-mm main tube is in a different price range, with an MSRP of 2,819 euros and also has to prove itself here against the well-known competitors from German-speaking countries. The compact long-range optic has the same "Dev-L" reticle, but in addition, the interesting "LevelPlex" system. The digital "Anti-Cant" system is intended to prevent unintentional cant. The horizontal position is especially important for really long shots. The system is switched on and off by pressing the button. This button is in fact the battery housing including the cover. In the scope, you can see one of the two arrows light up at the edge if the scope is not exactly level. This is a fine thing, because it allows you to observe the horizontal position at the same time as you are observing the target. When observing a bubble level mounted on the mount or scope, this is often not possible. By means of a menu, which is activated by pressing the button for three seconds, it is possible to adjust the luminosity of the arrows and the precision. For the latter, you can choose whether the difference from the horizontal is one or half a degree. The "LevelPlex" function is of course also helpful in mounting the scope correctly. In professional long-range use, you still need a level or a clinometer (level box) to position the rifle horizontally first! 

Elevation and windage adjustment of the SIG Sauer Electro Optics Tango6

Disassembled Tango6 elevation adjustment
Disassembled Tango6 elevation adjustment: the cam that forms the stop of the freely adjustable "zero stop" is visible on the brass cylinder, which is attached to the elevation adjustment shaft by means of grub screws. The locking body is attached to the axle with an Allen screw.
The Tango6 and the Tango4
The Tango6 is assembled in Japan, the Tango4 in the Philippines.

SIG Sauer Electro Optics promises an elevation adjustment range of 22.3 Mrad (223 cm/100 m) for the Tango6. To check, we took off the turret cap, removed the latch and stop, and adjusted to the maximum – at 210 clicks, at least on our test scope, it stopped. This means that the long range shooter is best off mounting this scope with forward tilt. The windage adjustment offers sufficient possibilities with 14.0 Mrad measured by us. Corrections to the elevation and windage turrets can only be made if you have unlocked the lock function. Some manufacturers do not lock the turrets because deactivating them can be frustrating under time stress. SIG Sauer, however, has solved the matter neatly. After all, there's no need to handle a small turret with a heavy-duty lock here, but rather an elevation turret with a sturdy, black anodized light alloy cap with a lush diameter of 41 millimeters. By the way, these 41 millimeters provide enough space for 120 clicks within a 360-degree turn. To release the lock, you simply push the turret up or to the right (windage turret). Without spring pressure, simply push about 7 millimeters out of the toothing, after which the turret can be adjusted precisely with suitable friction. After adjustment, snap the turret back into place – and you're done. The advantage? Because of the lock, the adjustment can be made somewhat smoother. Without the lock, a heavy spring pin must be used so that the turret does not move unintentionally if the shooter bumps into something during position changes.

Test: Tango4 and 6 – image quality, illuminated reticle and zero stop  

Tango4 eyepiece with mounted throw lever
Tango4 eyepiece with mounted throw lever, which is a standard accessory. Unfortunately, this cannot be mounted on the Tango6.

The image quality of the Tango4 is quite appealing. Our test target is easily recognizable at 100 meters, even the grid consisting of 0.2 millimeter thick lines is identifiable. For our evaluation, we always take the same target and photograph it through the scope at 100 meters. This allows us to evaluate and compare the results at our leisure. This revealed that the image quality of the Tango6 is on a much higher level. In terms of resolution, this scope can keep up with the usual suspects in the top league at thirty times magnification.

The integrally illuminated "Dev-L" reticle of the Tango4 and 6 is less suitable for hunting grounds use, as it is well known that in twilight to nighttime shooting is only at close range, which means that additional hash marks are not needed. In addition, you want as little extraneous light as possible, so a small dot that is only softly illuminated is probably the best option.

We liked the Tango6's motion-activated "Motac" illumination. The reticle illumination turns off after 4 minutes (manufacturer specs 6 minutes). However, if the Tango6 experiences the slightest movement, regardless of position, the illumination turns back on immediately.

SIG Sauer Tango4 and Tango6 specs and pricing 

Technical data:

SIG Sauer riflescope  
SIG Sauer riflescope
Tango 4Tango 6
Length (mm): 
Weight (g): 
Main Tube Diameter (mm): 
Ocular Length  (mm): 
Ocular Outer Diameter (mm): 
Objective Outer Diameter (mm): 
Field of view (m at 100 m): 
Exit pupil in millimeters: 
Diopter adjustment range: 
Eye Relief (mm): 
Parallax Compensation: 
Parallax Free Adjustment (m):
45.7 (50 yd) - 
27.4 (30 yd) -
Adjustment per Click: 
0.1 Mrad 
0.1 Mrad
Total Elevation Traverl: 
17 Mrad 
23.2 Mrad
Total Windage Travel (100 m): 
8.5 Mrad
14.5 Mrad
Dev-L Mrad 
Dev-L Mrad 
Reticle Illumination:
Auto Power Off: 
Water Resistance: 
Reticle Focal Plane: 
1,009 euro
2,819 euro
the reticle of the Tango6
Even at 5x magnification, the reticle of the Tango6 can be used. At 100 yards, you can see a fine cross, with the essential markings still visible. Exact aiming with the cm marks becomes a bit more difficult, of course, but there is a rich field of view of a good 6.3 meters and considerably more depth of field.

Our test conclusion: how do the two SIG Sauer Electro Optics Tango4 and 6 models perform in practice?

Overall, the Tango riflescope series from SIG Sauer Electro Optics impressed us. The Tango4 with the successful "Dev-L" reticle is suitable for long-range shooting when mounted with a forward tilt. It convinces with a good price/performance ratio.

The very good, high-performance Tango6 with identical reticle has a unique selling point with the "LevelPlex" function. In terms of overall elevation adjustment, other scopes often have more to offer, and with a price in the 3,000 euro region, it has to compete against strong competitors with even more established brand names.

One final thought: another plus of SIG Sauer Electro Optics is and remains the "system provider" topic. Of course, an optic from SIG Sauer looks particularly good on a gun of the same brand.

For more information about the manufacturer's products please visit the SIG Sauer website.

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