US Optics SN-4S Review

Posted by on February 1, 2011 in Accessories, Gun Reviews, Optics, Rifles |

SN-4S on SCAR 17s


The 1-4x optic is an optic that is gaining popularity in both tactical applications and competitive venues.  From CQB to medium range engagements, the 1-4x optic is extremely versatile for tactical applications. For 3-gun competitions it provides the competitor a quick option for both his/her close targets to ones out to 400 yards.

With all the hype around Nightforce and Trijicon, I feel that US Optics is sometimes left behind in the quality optics discussion.  US Optics has had contracts with the USMC and many law enforcement agencies, so most hardcore shooters and long range forum regulars know about them—I feel their recognition is far less for Joe the average shooter even though the typical range warrior will know about Trijicon or Nightforce whose prices are similar.

Although I’ve shot with Trijicon’s Accupoint 1.5-4 (I haven’t had a chance yet to try out their newer true 1-4), and I’ve had some experience with Nightforce’s NXS 1-4, I’ve never had the pleasure of shooting with a US Optics scope.   So when Jeff Fertal at US Optics offered us a SN-4S to review, I jumped at the chance.  I’ve only seen their scopes on display, and I was thoroughly pleased with my initial impressions, so finally getting to shoot with one for a couple of months was a real treat.  After using the US Optics (USO for short) SN-4S on an AR-15, Bushmaster ACR, and a FNH SCAR-H, I’m finally ready to give readers my feedback and introduce them to a quality 1-4x optic that I think has been overlooked by many shooters out there.                                                  click read more to continue the review

1-4x US Optics


Upon initial handling of the USO SN-4S I found the 8.5 inch optic to be built like a tank.  Being that its constructed from 6061-TB aircraft grade aluminum, and a lot of it considering it feels very dense, it’s no wonder that US Optics feels confident enough to throw it off the top of a building, mount it, then shoot with it as I saw on one of their product demo videos.  The scope just feels solid, plain and simple—its construction is among the most durable I’ve witnessed and I’m willing to bet any shooter that handles the USO SN-4S will feel confident that the scope can take some abuse.

Since the USO SN-4S is more durable than any other 1-4 optic I’ve handled it is also the heaviest.   Compared to the Nightforce NXS 1-4 it’s about 30% heavier, coming in at just over 20 ounces compared to the Nightforce NXS’s 17 ounces.  It’s almost always a give and take when comparing anything; if you want tank like durability, then you have to be willing to add a little more weight to your rifle (something many shooters are reluctant to do).  If I had to complain about one thing with the SN-4S, it would be the weight, but then I take into consideration what US Optics’s CFO Nick Baroldi told me regarding the weight, “if a few ounces is that big of a deal for you, then take out a few rounds from your magazine;”  well played sir.  I would have to say the juggernaught durability completely justifies the few extra ounces.

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As mentioned before, many times, the SN-4S is solid all the way around, including the windage and elevations knobs.  Both the windage and elevation on this particular SN-4S are 5/8 MOA adjustable and the knobs feel as durable as the scope’s housing.  The clicks have very strong tactile feedback, which lets the operator know without question he made the adjustment.  The knobs themselves have an abrasive edge allowing an operator a good grip to make adjustments.  Granted, a 1-4x scope should, in theory, only need adjusting once, and doesn’t necessarily warrant constant adjustment as do scopes built for long range shooting.  It should function as that 90’s rotisserie kitchen appliance infomercial—“set it and forget it.”

The USO SN-4S did just that; it held zero no matter how many rounds I sent down range on any given platform (5.56 and .308).  The only adjustments that were needed was when I switch from my AR-15 to the ACR (if memory serves me correctly, it only needed to adjust a few clicks).  When I switched from the AR-15 to the SCAR 17s, I believe a full revolution on elevation was needed, but it still held its zero after thousands of rounds.  So from the housing to the adjustment knobs, I would have to say the US Optics SN-4S is probably one of the finest built and most durable scopes I’ve had the pleasure to come across.

US Optics Review


All of US Optics scopes have a plethora of options that are available to potential customers.   One of these options (and probably the best aspect of customization available) is a choice of reticle.  The reticle I chose was the “Circle Chevron,” which is very crisp and easy to pick up.  There are also 3 other reticles available on the USO SN-4S, a circle dot, a fine crosshair, and a BDC reticule.   I chose the Circle Chevron reticle for one main reason—I wanted a reticle that was easy to focus in on right away.  The lateral lines combined with a center circle helps my eyes go directly to the POI mark of the ridicule (the tip of the triangle).  I find normal crosshairs with no overtly obvious visual reference to the center to be sometimes cumbersome when gaining a rapid sight picture.

The Circle Chevron reticle lends itself well to both targets less than 50 as well as targets out to 300 (the farthest range I tested).  Being that the reticle is etched on the front focal plane, the MIL representations of the reticle “subtend”, which means they stay true no matter what zoom level the scope is set to.  This comes in handy with longer range targets, where the range finding portion of the reticule would be needed.  A shooter can estimate a targets range (assuming the target is an average human silhouette) by lining up the target’s shoulders with the appropriate range finder.  Each set of lines represents 17 inches (average shoulder width) at that range.

What I found to be peculiar is that Circle Chevron reticule doesn’t include a BDC out to 600 yards while it provides range estimation up to 600 yards.  An experienced shooter (and US Optics are designed for experienced shooters) could guesstimate effectively a shot out to 600 yards with the SN-4S.  For 300-350 yard shots with my AR-15, I was using inner diameter of the bottom of the circle which proved to be effective.  Although a BDC would be nice, I fear that it would make the SN-4S Circle Chevron reticule too busy, which would turn off many shooters.

US Optics also allows a customer to purchase a lit reticle for their scope which was an option we chose on our SN-4S.  If you have the option installed, turning it on is done by rotating the dial on the left hand side of the scope body.  The dials have the same feel as the elevation/windage knobs with a nice, strong click to them.  The dial itself has 11 different settings, 11 being the brightest.

Now while the SN-4S is a true 1-4x optic, and has a lit reticle, it will not replace your red-dot if that is your preferred optic.  First off, the lit reticule is only good for low light situations such as dawn/dusk, or indoors; the operator will not be able to see the lit reticle in complete sunlight.  I can say that battery life has to be pretty good, considering I left it on once after a range visit and didn’t notice until about 14 hours later.

USO 1-4x

Another reason the SN-4S can’t replace the functionality of a red-dot is that acquiring the reticle is not as rapid as it is with an Aimpoint or Eotech—yes, the SN-4S is a true 1x optic, but acquiring the reticle on the SN-4S at 1x compared to getting a rapid sight picture on a red-dot, well, hands down the red dot wins.  When using variable zoom scopes, there will always be eye relief and parallax issues, the only difference is how much, and that difference directly translates into the price of the optic.  I believe it’s a better solution than using a clunky setup like a magnifier behind a red dot to be able to reach out; but for shooters (such as myself) that have grown accustomed to the rapid target acquisition aspects of their Aimpoints or Eotechs, will find the 1x setting on the SN-4S doesn’t quite match up.

The one aspect that will set a scope apart from another is the clarity of the glass; this is an area where US Optics fails to disappoint.  The optical clarity on the SN-4S is probably the best I’ve seen—the photos do it no justice.  It’s a fine line when comparing US Optics glass to Nightforce and Trijicon’s Accutpoints, the pickiness factor really needs to kick in; however, I would have to give the title to US Optics.  I tried my best to capture just how good the glass is, but despite my efforts, the pictures just don’t illustrate the experience of looking through US Optics glass.  The 30mm tube does an excellent job of capturing light, giving the operator a crystal clear picture.  Even in low light on 1x magnification, the SN-4S’s glass is extremely clear with virtually no distortion.

The eye relief is an adequate 3.5 inches according to the spec sheet US Optics sent me; and for all accounts, it seems to be accurate.  While dialing through the different magnification settings by rotating the eyepiece (which by the way is just as durable as the rest of the SN-4S and has a very smooth rotation) the eye relief stayed constant.  With the same cheek weld on my rifle while increasing the zoom, I could still see through the flawless glass with no “tunnel vision” experiences or eye relief issues.  The sight picture stayed consistent, the reticle was crisp, and the light capture was great no matter what magnification level the SN-4S was on.

USO SN-4S review


The SN-4S from US Optics was an absolute joy to shoot with.  The clarity of the glass really sets it apart from other optics out there, even optics that are in a similar price category.  All the functions of the SN-4S work as one would expect from a high end optic.  The dials have a crisp tactile feel, the transition to higher magnifications is quick and smooth, and the lit reticle serves its purpose in low light.  The only reservation I have is with the weight; however, I’m willing to overlook that issue since the weight vs. durability ratio justifies the slightly heavier feel.  Even though it’s very crisp and clear, the reticle is pretty small at 1x zoom, due to the fact that the reticle is on the first focal plane.  If the lit reticle could be visible in direct sunlight, it would make it less of an issue since the reticle would be easier to pick up.

One of the best things with US Optics is that their scopes are completely customizable—from reticle type to color, from elevation/windage knobs to eyepiece, if you have the money, US Optics will build you the scope.  The base price of the SN-4S is $1170 (around $1400 as tested, even more if more options are selected such as color), and for the money I believe it passes its competitors.  The glass is slightly better than the similarly priced Trijicon Accupoint series and the Nightforce NXS, but not by a wide margin, however it is slightly noticeable.

I would like to stress the outstanding durability of the USO SN-4S again.  The once piece 6061-T6 aircraft aluminum scope body is the toughest I’ve ever seen on an optic.  Our writer Alex told me that when US Optics was giving a demonstration to him and his USMC buddies, the US Optics representative took the scope off a rifle, hammered a nail into some wood with it, then mounted the scope and fired it dead on—demonstrating the durability of the scope and its ability to maintain a true zero.  When talking to the US Optics rep at SHOT SHOW, and how he would clear the reticle if dust happened to get on the lens from the inside, he proceeded to bang it on the table as hard as he could then stating, “that’s how I would do it…”

So along with an almost indestructible durability, the SN-4S is a crystal clear optic, which has a true 1x magnification with virtually no distortion at 1x, and it performs flawlessly as one would expect.  For tactical use, 3-gun competitions, or someone that has a need for a versatile optic, I think any shooter that mounts a US Optics SN-4S on their rifle will be completely satisfied with their choice, and will probably own the optic for their entire life being that the scope will probably outlive them.

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