In order to stay relevant in the market place, every major company has to continue to evolve their products to match changing demand and innovation. This applies to scope manufacturers as well. We constantly see the steady stream of newly released products each year as designers strive to stay ahead of all of their competitors and gain market share. Over its lifetime, Sightron has only been luke warm about committing to the dedicated tactical genre of scopes, but that seems to have changed recently and the release of their S-Tac line of scopes shows a stronger commitment to the genre. We decided to take an in depth look at this line of scopes to see how they stack up as a full duty ready long range tactical scope. The S-Tac line has seven different models, each with several reticle and knob options. The one we have here for review is the 3-16x42mm with MOA knobs and matching MOA-3 reticle.
The scope comes in the standard Sightron box and includes a neoprene cover, lens cloth, Allen wrench, and a basic sheet of instructions for the reticle. This instruction sheet simply includes the substension list for the reticle and how to do basic range estimation calculations using the MOA reticle. There is no other provided instructions for the scope itself. The neoprene ScopeCoat cover is fine for storage, but would be set aside anytime you head to the field. We don’t put a lot of value on the packaging of scopes as typically it all gets discarded and we would rather the company apply their funds toward either better scope features and quality, or lower cost to the consumer. Some sort of instruction or maintenance manual might be nice, but it is the 21st century and most all that stuff can be found online. Checking on the bottom of the scope we find that it was manufactured in the Philippines, normal for Sightron and a common country of origin for good mid range scopes.
The eyepiece on this S-Tac scope is a fast focus design that is of moderate size. There is a rubber ring on the end, as usual, to prevent major injury in the event of a scope kiss. This scope has a pretty good eye relief range, right around 4″, which should help prevent that kiss. The entire dioptre adjustment range is covered in about 1.7 rotations and it has moderate levels of friction to hold it in place. There is no indicator mark on the eyepiece, but that is typically not needed. Just rotate until the reticle is clear and sharp when looking at a blank wall, and then be on your way. The ring has very minor serrations on it for a gripping surface, but it seems to provide enough grip to adjust it without problem.
At the front of the eyepiece is the large zoom power adjustment ring with markings from 3x to 16x. We like this adjustment range as it provides a very broad range suitable for most sniping. It is high enough to see the detail needed for engagements well beyond 1000 yards while not too much zoom to kill the field of view and light gathering ability. The ring itself has very large knurling on it, so large that we would classify them as ridges. They provide a great gripping surface making it very easy to adjust the zoom power. In addition to those ridges, Sightron has incorporated a flip up throw lever. The throw lever rotates up, but does not lock, which means it can inadvertently get flipped down fairly easy and it only works ‘okay’. Chances are it will be left in the flipped down position since those ridges provide such a good gripping surface on their own.
The zoom ring adjusts smoothly through the entire range with only moderate amounts of force required to move it. The reticle is located in the second focal plane so the hash mark sizes are only accurate at one zoom range, which on this S-Tac scope is at the max zoom of 16x. There is not any sort of marking on the zoom ring to indicate what power should be used, but it should not take much to remember to just crank it up to the max zoom and go. The actual number markings on the ring are tilted slight toward the operator to help with seeing them from behind the scope. In front of the zoom rings the 30mm tube provides a somewhat short 1.9″ (48mm) length for which to mount the rear scope mounting ring.
The tube is a nice one piece aluminum tube for durability and the shoulder area where the adjustments are mounted is a rounded shape with a flat bottom, where the unique serial number for each scope is printed. The elevation and windage knobs are a medium size and have large dust covers that fit over them. They are large enough that leaving the dust covers off and using them as an external knob is feasible. There is some light knurling at the top of the knobs to help provide a good gripping surface, but it is pretty minor in order to help the dust covers fit over the top. There are 15 MOA of adjustments per revolution and the numbers are nicely marked on the knob with hash marks at each .25 MOA. There are also horizontal lines under the knob to help track how many rotations have been dialed in. There is no zerostop feature, nor are there any markings visible from behind the scope indicating which way is up or down.
The clicks are semi-muted and feel decent and are pronounced without mushiness, though there is some minor movement of the knob before the click engages. The factory indicates that there is 70 MOA of adjustments on this scope for both elevation and windage and our test scope had 70.5 of elevation, almost exactly what they indicated. One thing that is interesting to note is that the horizontal lines under the turrets have numerical markings on the right hand side, the middle is marked 0 and then there is a 2 marked on the 2nd line down and 2nd line up. It is nice to have reference points, but a majority of these scopes are likely to be mounted with a 20 MOA canted base which immediately will throw those indicator numbers off. We are not opposed to have numbers to count the lines, but it would be smarter to just start counting from the bottom and not the middle.
The windage knob is the same size and shape as the elevation knob and has the same 15 MOA per revolution. The markings go up in only one direction, right, and there are lines under this knob as well, which is a bit unusual for a windage knob. The clicks feel the same with that same minor movement before the definitive click. The two knobs both have three small Allen set screws in the top which can be loosened and then the knob slipped to zero once the rifle and scope have been zeroed at the desired range. All in all the knobs are pretty good with good enough clicks and the dust cover feature is nice for field use and a good option.
Opposite of the windage knob is the side focus which has a larger diameter and is short. This knob does not have a cover and has a much more aggressive knurling on it to provide a very good gripping surface. The full adjustment range covers about 75% of the knob and the markings do not use ranges but just a growing scale type of marking system with the infinity mark at the very top. The large diameter knob gives a significantly larger adjustment range than a smaller diameter knob allowing for more precise focus adjustment. It seems trivial to use a larger diameter knob, but it actually seems to work well and we liked it. Unfortunately, Sightron elected to have the scope focus all the way down to 9 yards which takes up a chunk of that focus range. We would rather them have started at 50 yards and then allow for more granularity in the adjustments along the entire range.
This particular version of the S-Tac does not have an illuminated reticle so there are no additional controls on the scope. In front of the shoulder area there is about 2.25″ (57mm) of tube length for which to mount the forward scope mounting ring. The area for mounting rings is only moderate both front and rear so the use of a one piece rail is likely necessary on some long action rifles in order to properly place the scope. At the front the tube, it tapers up into the objective lens bell housing which houses the 42mm diameter lens. The bell is threaded, but no sun shade is provided with the scope. You can purchase a 3″ long sunshade for about $30 (Sightron item #70011).
The finish on the scope is a matte black anodized finish and there are not a lot of external markings on the scope. This gives it a very purposeful and tactical look. The scope is a smaller size than many modern high power scopes and measures only 13″ long and weighs about a pound and a half. It has good proportions and is a nice looking scope. Sightron says it is fully water, fog, and shock proof and they cover it with their lifetime warranty.
The reticle is what Sightron calls their MOA-3 reticle, which obviously is a MOA based design. It uses various sized hash marks to indicate the MOA markings. The distance between the hashmarks is 2 MOA with larger hashmarks every 10 MOA. Sightron provides a reticle sheet that has all of the measurements of each of the hash mark heights and various other dimensions to help an operator be more precise with their measurements. At the center of the reticle is a small floating dot that appears to be the same diameter as the crosshair stadia lines are wide. The reticle is a clean design without a lot of clutter. There are no heavy stadia on the edges that is sometimes useful to help focus the eye on the center reticle when observing busy backgrounds, but the reticle seems to work pretty well enough as is.
As mentioned earlier, the reticle is located on the 2nd focal plane and the scope must be set to 16x for the measurements to be accurate. There is also the option of setting the scope at 8x which then doubles the size of the measurements, making the spacing 4 MOA between hashmarks. Additionally, you can set the scope to 4x and quadruple the measurement sizes (8 MOA between hash marks). You have options.
The optics use Sightron’s Zact-7 Revcoat multi coating on all the lenses and while we cannot tell you if that is better than anyone else’s coatings, we can tell you that the optics are pretty good for the price range of the scope. The optics are bright with good definition and contrast to the edges, but anymore, most scopes are that way. The really high end glass on the top of the line scopes is exceptional, but the mid quality glass has made major improvements over the years and it work well on these lower mid range scopes.
For our operational range tests, we used a set of Leupold medium height Mark4 steel rings and mounted the scope to our Remington 700P test rifle chambered in .308 win. The rifle has a steel 20 MOA canted Warne base on it which makes it easy to properly space the rings to fit the scope. Everything mounted up quickly and easily and it was time to head to the range. If you have not read how we conduct our scope tests, take a moment to read our article How We Test Rifles and Scopes.
We like to use Federal Gold Medal Match ammo with this rifle as it shoots right around .5 MOA giving us good measurements for our scope tests. The weather was a brisk 40 degrees on a bright sunny morning. Zeroing the rifle and scope was easy enough and even with the scope on 16x it was no problem to focus the scope at the 25 yard target, or even closer, just like Sightron indicated it would. The testing began with the box test, firing a 5 MOA box to test tracking and repeatability, both of which performed well.
The click size test was up next. We fired the first group, dialed in 20 MOA of left, fired the second group and then dialed in the 20 MOA of right and fired another round to insure it came right back to the initial zero, which it did. The first group was a tad over .6 MOA center to center and the second was right at .5 MOA. The distance between the center of the two groups measured 21.2″. At 100 yards where the groups were fired, 20 MOA measures precisely 20.94″, which means there was only 1.2% error, an excellent result for this test. Sightron calls their internal tracking system the ExacTrack and claims it to be the most precise tracking system on the market. We do not know what is involved with that system that would be any different than what other scope makers use, but it does seem to be very accurate and precise.
While using the scope in the field we thought the optics were good and performed on par with other scopes in this scope’s class. We did not like the flip up throw lever. Its sharp corners were not comfortable to use when flipped up and it often times would try to flip down while we were using it, and in the end, we left it down and didn’t bother. It is a nice idea, but not quite as usable as we hoped. We checked the reticle size against some measured points and on 16x the reticle was right on and it is nice to have the reticle and knobs work in harmony with each other.
Our final operational tests include testing for reticle drift with both the zoom control and focus adjustments. With the bore sighting grid attached to the rifle we first tested to see if the reticle drifted at all when adjusting the scope through the entire zoom range. The results were good. The reticle was very solid and stayed planted right on the grid intersection we had set it to. We then tested the same thing with the focus, going from a close focus all the way to infinity and back several times to see how it did. Our results revealed an issue that we often find with scopes that try to focus the parallax in too close. The reticle was pretty solid from the focus range of about 30 yards to infinity, it drifted maybe a total of .5 MOA through that entire adjustment range. But from the 30 yard focus down to its closest, at about 9 yards, the reticle shifted at least one full MOA, if not more. This seems to be an issue on any scope that tries to have that super close focus range. This is a big reason why we would prefer that they not do this and instead have a parallax focus that starts at 50 yards and goes to infinity. It’ll be more precise and they could allow for a knob to rotate the same amount and then giving finer granularity. This issue is not critical since for sniping purposes we are always shooting at ranges beyond 50 yards so the drift doesn’t effect us, it just seems a bit wasted.
For a $500 scope, the S-Tac 3-16x42mm MOA scope actually performed nicely. The design is good, the size is not too large, the 70 MOA of adjustment is adequate for mid range sniping and shooting, the knobs track well and the optics are nice. Though there are things we didn’t like. We would like to see the windage knob count up in both directions, get rid of the flip up throw lever, knobs without the little bit of slop between the nice clicks, and of course the preference of a focus knob that started at 50 yards on this long range scope. The negatives certainly do not out weigh the positives and we would certainly feel comfortable putting the scope on a rifle and heading out. It is nice to have another mid price option that we are comfortable recommending. Their 5-20x50mm and illuminated models may also be worth looking at. It may not be a five star scope, but it is a solid three point five.
Sniper Central 2018