SIG TANGO6T SDMR 1-6x

Low power variable optics, which zoom from 1x to 4x, 6x, or more, have surged in popularity for their great versatility, whether for military, law enforcement, competition, defensive, or recreational use. At 1x, with a well-designed reticle and bright illumination, they function nearly as well as a red-dot sight. And dial up the magnification for precision shots, distant targets, positive target identification, or a better view.

3-gun competitors have relied on LVPOs to win matches for years, hosing close targets and ringing steel at distance. Special operations units have also fielded them, and they’re now trickling down to wider use. SIG Sauer has notched three contract wins to supply its TANGO6T 1-6x scopes to our military. Just a few months ago, SIG scored the Direct View Optic (DVO) contract to outfit the U.S. Army’s M4A1 carbines, reportedly for around $77 million. In 2018, the TANGO6T was selected for the Squad Designated Marksman Rifle (SDMR) and the USSOCOM Squad-Variable Powered Scope (S-VPS).

The S-VPS has a second focal plane (SPF) reticle, and the SDMR and DVO are first focal plane (FFP). SIG has delivered roughly 7,000 SDMR units to the U.S. Army and Air Force. The TANGO6T SDMR is now available for civilian purchase. 

SDMR

The new SDMR is a 1-6x24mm riflescope with a 30mm main tube. It features extra-low dispersion and high transmittance glass as well as an IPX-8 waterproof rating when submerged to 20 meters. It’s rugged, robust, and FDE.

The SDMR is shown mounted in SIG’s matching ALPHA4 mount, which is light, slim, and clamps securely with two bolts, but not yet available for sale. Mounting the TANGO6T is very easy; using a scope mount with horizontally split rings, simply line it up with the reference line on the left side to level the scope — no need for bubble levels or leveling tools.

The zoom ring is smooth, with just enough resistance. For more leverage, attach the throw lever that SIG includes with the scope. And in another nice touch, SIG embedded two green fiber-optic tubes in the zoom ring, to see at a glance where you have it set.

As the TANGO6T is designed for close and midrange engagements, the elevation and windage turrets are capped. They adjust in 0.2 mil increments, with positive and tactile clicks. Loosen a set screw to reset zero on the adjustment dials once you’ve zeroed the scope.

RETICLE

With a scope like the TANGO6T, you rely on the reticle to get your work done, so its design is important. SIG’s DWLR-6 reticle in the SDMR is a FFP, BDC design, prioritizing tactical engagements. Thick stadia on the outskirts at 3, 6, and 9 o’clock help draw your eye to the center, which has a 0.3 mil center dot surrounded by a thick horseshoe. There are horizontal marks at 3 mil intervals to lead moving targets and a tree below for holdovers on distant targets. The tree stretches out to 1,000 meters, based on the ballistics of M118LR 7.62 ammo. 

The horizontal bars that decrease in width down the tree represent 18 inches at the given distance, so you can estimate the distance to an average-sized human. In practice, you would acquire the threat in your scope, then match up his shoulders with the horizontal bar closest in size. That provides an estimated range, and if your ballistics match up with M118LR, just slide a bit up or down the tree to the appropriate hold over to break your shot. The dots to the left and right provide 5 and 10 mph wind holds. 

The DWLR-6 reticle provides a lot of useful features without being overly cluttered. And because it’s FFP, you can all of them at any magnification setting.

ILLUMINATION

Powered by a CR2032 battery, the center dot and horseshoe in the reticle are illuminated. At 1x, the FFP reticle is tiny, so illumination is very important to pick it up quickly; it looks kind of like a hollow red dot. At 6x, the reticle grows; you may find you’ll want to turn down the illumination from where you had it at 1x. There are 11 brightness settings, with 2 for night vision. The control dial is on the left side, with a full rotation to cycle through all brightness settings and an off position between each. Pull the ring outward before rotating it, then push it back in to lock in place. We prefer this type of control much more than push buttons. 

AT THE RANGE

The TANGO6T’s glass is clear and bright. At 1x, there’s a bit of distortion as you pan around; we were able to reduce it by tweaking the diopter adjustment. Unfortunately for us, eliminating the distortion didn’t coincide with properly focusing the reticle, so we had to compromise.

The eye box at 1x is pretty roomy. It’s easy to obtain a good sight picture, though like all LVPOs, it’s more challenging in unconventional positions or on your support side. At 6x, the eye box naturally shrinks a lot; it’s important to maintain a consistent cheek weld. 

The DWLR-6 reticle works well for its intended purpose. Adjustments tracked accurately, and we readily rung steel at distance. Preferences in reticle design depend on use case and are hotly debated; many RECOIL staff are partial to mil scale reticles to hold exact amounts based on our dope for specific loads. However, BDC reticles are simple and quick to employ, and it makes sense to find them on issued weapon systems. It’s also pretty straightforward to translate your particular setup to the subtensions on a BDC reticle.

At 1x, the TANGO6T’s brightest illumination setting equates to between 9 and 10 on an Aimpoint T-1, plenty daylight bright for our more eagle-eyed staffers and just bright enough for our resident Mr. Magoo. We’ve run SIG’s FFP and SFP versions back-to-back, and as you’d expect, the SFP models are a little brighter.

LOOSE ROUNDS

SIG has taken some flak on the interwebs over the years for overseas-sourced products. But SIG is building more and more of its optics domestically each year. We recently visited SIG’s Oregon facilities; rest assured that while some components are from overseas (as with all optics companies), TANGO6T scopes are assembled and quality-tested here in America. We suited up in a full-body condom and watched workers assemble them in SIG’s Class 1000 cleanroom.

We expect the TANGO6T SDMR will serve our warfighters well. It’s very thoughtfully designed, and if you’re seeking a duty-grade optic, you should take a serious look at one. If you like what you see, but wish it were SFP or had a different type of reticle, don’t despair; SIG offers other variants with different combinations of BDC, mil, or MOA scale reticles in the first and second focal plane. 

SIG SAUER TANGO6T SDMR 1-6X24

Focal plane: Front
Tube diameter: 30mm
Adjustments: 0.2 mil clicks
Total elevation: 36 mils
Length: 10.7 inches
Weight: 21.9 ounces 
MSRP: $1,820 
URL: sigsauer.com

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