Review: Primary Arms MicroPrism Optics

By GunSpot

In today’s test, I review some of Primary Arms’ MicroPrism optics. The two on the test bench today are the SLx 1X MicroPrism and SLx 3X MicroPrism. These optics are relatively new to the market, with the 1X coming out in June 2021 and the 3X releasing in February 2022. These optics were a fantastic addition to Primary Arms’ ever-expanding line of optics. Primary Arms has made it clear that they are here to stay and that they are a serious contender in the optics world.

These Primary Arms MicroPrisms are part of the SLx optics line. According to Primary Arms, the SLx optics are built with a reputation for innovation, reliability and value. All Primary Arms SLx optics undergo rigorous field testing during development to best serve you in any environment.

Build Quality

The SLx 1X MicroPrism has a minimal form factor. Frankly, it’s something that’s not much larger than the body of an Aimpoint T2 red dot.

The body feels sturdy and has 1 MOA adjustment for windage and elevation. The elevation adjustment is on the top of the body, and the windage adjustment is found on the side. Both can be adjusted easily with a flathead screwdriver or similar object. The optic has 120 MOA in elevation and windage adjustment.

On the opposite side of the body is the battery compartment and illumination adjustment for the reticle. A single CR2032 battery powers the optic’s illumination, and that battery can last for 25,000 to 50,000 thousand hours.

The optic’s rigorous field testing included testing with more than 7,000 rounds fired while mounted on a .308-chambered rifle. For an optic with a micro-sized body like this, that’s a highly impressive feat.

The SLx 3X is a lot of the same when we talk about the build quality. It has all the same controls in the same spots, but on a larger scale. The optic is still in micro size, as its name suggests. All in all, it’s probably a bit larger than a Trijicon MRO. This optic and the 1X both have threaded tubes that accept an anti-reflection grid known as “kill flash.” Kill flashes for the 1X and 3X can be found on the Primary Arms website.

Mounts

One of the most impressive elements of the optic is the range of mounting options included in the package. Eight different optic mount options are in the box, comprised of cantilever spacers and straight spacers that can be mixed and matched to achieve heights that range from 1.1” to 2.075” tall.

Once you find the desired height, the manual recommends that you tighten the screws to 25-30 in.-lbs. The cross bolts on the removable base should be tightened to 55-60 in.-lbs. with a T25 Torx and a blue thread lock applied.

Reticles

The illuminated reticles in both optics are ACSS-style reticles for which Primary Arms has become well known for putting in their optics. Specifically, the 1X features the ACSS Cyclops Gen II reticle.

The 1X reticle has different ranging distances for 5.56mm, .308, 7.39x39mm, 12 Gauge 1 oz. slugs, and 300 Blackout (both super- and subsonic). The circle part of the reticle represents a shotgun pattern at 25 yards. There’s tons of information built into this reticle, allowing you to use it with multiple calibers at many different distances.

The SLx 3X MicroPrism has a reticle that is similar to the ACSS found in the SLx 1X. However, the reticle found in the SLx 3X is the ACSS RAPTOR 5.56 Y. This reticle has a chevron, wind holds, and drops that can be used with 5.56mm, .308, 7.62x39mm and 300 Blackout.

We shot it on the Hellion, chambered in 5.56 with a 16” barrel. We zeroed the bullpup at 100 yards for this caliber and barrel length. On the ACSS RAPTOR, this made the chevron point accurate at 100 yards, with the inner point ranged for 200 yards and the chevron feet representing 300 yards. Then, the bottom hashes go to 400, 500 and 600 yards.

Laterally from each of these hashes are dots for wind holds at those respective distances. The inner dots represent a 5 MPH wind hold, and the second one represents a 10 MPH hold. Each of the hashes can also be used to range a target. The hashes measure 18” wide at their respective distance. The 18” width is, on average, the width of center mass, just like an IPSC target, so you should be able to match up the hashes to a target and then determine how far it is.

Performance

I first started with the 1X on the range and was delighted with its performance. As you might have imagined, the 1X has a very generous eye box. It’s not unlimited like a red dot, but in all honestly, it might as well be. The eye box is so huge that even with my cheekweld way at the end of the stock, I can still use the reticle. So, if you are at the appropriate height as you present onto the target, you will see the reticle. The field of view is fantastic also, with it being able to see 76.5 ft at 100 yards.

When illuminated to the max, I can confirm that the reticle is daylight-bright. The etched reticle is fantastic, crisp and clean, and extremely easy to shoot accurately with it. I shot about a 3 MOA group with my SAINT at 100 yards, using reloaded ammo and the 1X MicroPrism. It’s extremely easy to pick a point and aim with the tip of the chevron.

The adjustments of this little scope are also fantastic. They feature nice audible and felt clicks. The adjustments are relatively easy, but hard enough that accidental changes are unlikely. The adjustment knobs are also recessed into the optic and adjusted with a standard flat shape like a flathead screwdriver or an expended casing.

With the 1X, we shot out to 300 yards on IPSC steel and also were able to shoot quickly at up close targets. We really enjoyed using this small but robust optic.

The SLx 3X MicroPrism proved to be just as fantastic as the 1X, but in its own right. The 3X magnification is just one power level under the famous 4X ACOG, which makes this optic a great budget-friendly alternative. Because of the long service of the 4X ACOG in the military, we know having a rifle mounted with a similar power level like this 3X makes for a very well-rounded option that provides shooters with accuracy at intermediate to long-range while still being lightning-fast in close quarters. As we’ve mentioned, one of the best parts is that it’s micro-sized.

The 3X is crystal clear with a great etched reticle that has illumination capable of daylight brightness. In fact, it was bright enough for us to see outdoors on a sunny day shooting at white steel IPSC targets. The eye box is still very generous with the 3X, and the cantilever mounts make getting the ideal eye relief achievable with just a couple of minutes’ worth of testing mounts and heights.

Conclusion

These optics are great in nearly every way. The price point for the 1X is $269.99, while the 3X is $319.99. These MicroPrisms are at a very competitive price point, especially considering the quality. These reticles are also great for all-purpose shooting that seems to fit every popular semi-automatic rifle caliber and even shotguns.

I’m glad Primary Arms continues to innovate and update its line of optics to bring new solutions to customers. These are great additions that fill a void in the optics community. They are great optics for those on a budget, for shooters who want wide versatility, and for those who just want good-quality optics. I hope Primary Arms continues to innovate for results like this, and I suspect they will.

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Primary Arms SLx 1X MicroPrism Scope, Red Illuminated ACSS Cyclops Reticle, Gen II

Primary Arms SLx 3X MicroPrism Scope, Green Illuminated ACSS Raptor Reticle

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