Gear Review: Eotech vs. Aimpoint vs. Primary Arms Red Dot Scopes

Throughout my dedicated but chronically under-funded shooting career, I’ve spent plenty of time peering through budget-priced optics. Some of them, like an $80 Romanian POSP (manufactured in ages past by the legendary IOR Valdada firm) were ‘cheap’ only in price; otherwise they were rock-solid, crystal-clear and battle-ready. Others, like a $30 Japanese-made Tasco from the early 1980s, were surprisingly well made for their price and provenance, and certainly fit to mount on a working man’s hunting rifle. Others—many others—were utter crap . . .

Imprecise adjustments, fuzzy edge focus, fragile tubes, wandering zeros, and foggy innards are endemic among the cheapest grade of scopes. Many shrink-wrapped scopes will work fine, as long as they sit on a .22 rifle that you’ll never drop, freeze, or shoot in the pouring rain. Drop them, let them get too wet (for too long) or mount them on a 7mm Magnum, and they’ll give up their ghost-ring in a hurry.

So I’ve done my time with crappy cheap scopes. Now, thanks to our dear editor, I’ve recently spent trigger time behind the glass of some very fine and expensive scopes too. During my testing of the FN-SCAR 16S and the Armalite M-15, I got acquainted with an Aimpoint Micro H-1 red dot and an Eotech XPS-3 transverse holographic sight. The results were surprising.

Glossary: Red-Dot, Reflex or Holographic?

For the sake of clarity, let’s get our terminology straight. ‘Red-dot’ is the generic term for a typically non-magnifying optical weapon sight that superimposes a glowing reticule over the weapon’s point of impact at a chosen range. The glowing reticule has a ‘focus point’ of infinity, so that it is in the same focus as the target and you don’t have to squint for it like the front post of an iron sight. The reticule may be emitted by a laser or an LED, and may be a simple dot or an elaborate circle or bullseye.

A ‘reflex’ sight is a type of red-dot sight in which the reticule is typically beamed into the user’s line of sigh by the use of a partially reflective parabolic reflector, as in the middle illustration above. [ED: will there be a test after?] The parabolic reflector may be a single exposed lens on a Burris Speed-Dot, or at the end of a sealed optical tube on an Aimpoint. The use of an LED emitter can allow an extremely long battery life, measured in years, compared to the higher power consumption of a laser emitter. Reflex sights are parallax-free near their optical center, but can theoretically experience parallax at extreme viewing angles. [ED: I knew that!]

A ‘holographic’ sight uses a laser emitter to create a wider and more elaborate glowing reticule into the user’s line of sight.  The reticule is actually projected by a hologram inside the glass of the final prism.  Holographic sights purport to be completely free of parallax at all distances and viewing angles.

Aimpoint Micro H-1

The Aimpoint line of red-dot sights are the ne plus ultra of red-dot reflexology. Since 1997, Aimpoint has been providing red-dot optics to the U.S. Army, for use atop M4 carbines and various light machine guns. From the broiling heat of a Baghdad summer to the bitter cold of an Afghan winter, Aimpoint has earned the trust of our fighting men and women and of their leaders. Our budget here doesn’t give us the option of torture-testing Aimpoint scopes until they fail, but I’m comfortable relying on Aimpoint’s hard-won reputation for extreme reliability and durability.

Aimpoint says it’s waterproof to 15 feet, and I’ll take their word for it. Even if my community swimming pool were that deep (it’s not), I’m not sure I could dive deep enough to retrieve it from the bottom.  The Aimpoint was happy as a clam at the bottom of my full bathroom sink for several minutes, and that’s as wet as any scope of mine will ever be.

Dimensions:

The Micro H-1 is Aimpoint’s smallest reflex sight, and it’s tiny. Even with a beefy LaRue high-rise QD mount, the H-1 weighs only 5.7 ounces. It’s 2.45” long and 1.65” wide, and just tall enough (about 2.25”) to allow a lower one-third co-witness with standard AR iron sights. Co-witnessing is a good thing, since it guarantees that you’ll still be able to aim your rifle if the red dot dies, without having to remove the dead scope.

Ergonomics:

The on-off-brightness control sits on the right side of the scope body. The dial is indexed 0 through 12, and each setting has a tactile ‘click’ so your fingers know how many clicks you’ve dialed up. The dial stops at the maximum and minimum, which makes it easy to turn the scope off without having to look at it. With a CR-2032 coin battery life of five years (!) of constant use, however, there’s not much urgency in turning it off before you go to bed unless you’re Rip Van Winkle. [ED: Don’t give Sylvester Stallone ideas. OK, I’ll shut up now.]

The Aimpoint micro is so small and light that it won’t screw up the balance and handling of any rifle it sits on. Red-dot sights typically mount over the center of the receiver, and this is also the center of balance as well. Even with a high-rise mount, the Micro adds only a few inches of height and a third of a pound of weight to your favorite carbine. Those inches and ounces are well spent; your carbine will handle and point much more quickly with the Micro than without it.

Adjustments:

Windage and elevation adjustments are made by unscrewing the sturdy alloy caps, reversing them, and using them as keys to twist the adjustment dials. The dials and caps are both solid and precise, and the inside of the caps features a conspicuous arrow telling you which way is right or up. Aimpoint advertises that each click will move the point of impact ½ inch at 100 yards. Neither our test rifle nor my eyesight are precise enough to really nitpick whether each click at 50 yards was exactly 0.25” or only 0.22”, but the adjustments were good enough to get us centered on target quickly.   There was no loss of zero through many dis-mountings and re-mountings over the course of several hundred rounds fired.

Optics and Reticule:

The Aimpoint Micro series features a 20mm aperture, and the photo above shows that most of that aperture is true ‘clear aperture’ not occluded by internal mounting rings or baffles. (The Aimpoint is the scope on the right, BTW.) A 20mm window may not seem terribly large compared to the Eotech or to magnifying scopes, but the slim profile of the optical tube means that it doesn’t obstruct much of your vision. The glass is exceptionally clear and sharp. The partially reflective inner coating and the red outer coating impart a faint bluish tint when looked through, which does not dramatically darken the field of view.

Here’s a photo of the Aimpoint and the off-brand clone, each at maximum brightness. At a brightness setting of 1, the Aimpoint was dim enough to see in the complete darkness of my closet without ruining what dark vision I possess.

How bright does it really go? The picture above doesn’t quite convey the brilliant glory of the Aimpoint’s LED emitter. At maximum brighteness, it burned white spots into my vision, while shooting in direct sunlight and aiming into a field of snow. (Seriously.) If you want to turn the Aimpoint Micro to maximum brightness, you should wear tinted or polarized shooting glasses.

Precision:

At moderate engagement ranges, you can expect the Aimpoint Micro (or a similar well-made simple red dot) to triple your group sizes when compared to a high-powered crosshair telescopic sight. At 50 yards our SCAR test gun gave us 2” groups with the Aimpoint, and 0.65” groups with a 3-9x40mm scope. The 3 MOA dot blots out a 1.5” spot at 50 yards, and a 3” spot at 100 yards.

It shouldn’t be a surprise that red dots aren’t for varmint hunters, snipers, or benchrest shooters. Tactical carbines aren’t either.

Eotech XPS-3

The Eotech XPS-3 is a holographic weapon sight with a large aiming window and a large, elaborate reticule. Eotech holographic sights have been adopted and used by the USMC and by innumerable law enforcement agencies. Like the Aimpoint, the Eotech’s ruggedness and dependability is unquestioned. Its working parts are all encased in nearly indestructible resin, and the entire body is also covered by a thick alloy shield.

It claims to be waterproof to 33 feet (take that, Aimpoint!) and once again I have no way of testing that claim.  Marines trust them in amphibious operations, and my test Eotech didn’t seem to suffer from a short bath in my sink. Oorah!

Dimensions:

The Eotech may be indestructible, but it is not compact. Eotechs have always been large and heavy, and the ‘Transverse’ line was developed in response to that criticism. Instead of two AA or CR-123 lithium batteries mounted lengthwise, the XPS-3 features a single CR-123 battery mounted athwartships. It still weighs a hefty 11.1 ounces with the battery included.

Since the Eotech is designed to be compatible with the AR platform, it’s made to co-witness with an AR’s iron sights. The unit is a hair over 2” tall, 3.6” long and 2.15” wide.  The XPS-3 may be smaller than previous Eotechs, but it’s still big. For comparison, it’s an inch longer, half an inch wider and nearly a half-pound heavier than the Aimpoint.

The Aimpoint Micro can ride on anything, including pistols, but the Eotech’s weight can make a small carbine feel very top-heavy, and its width can make an AK (or a similarly narrow rifle) look like a python that swallowed a pig.  You could mount an Eotech on a handgun, but it looks simply ridiculous and handles even worse.

Ergonomics:

Unlike some previous Eotechs, the XPS-3 mounts its controls on the left side instead of the rear, and I found them much easier to reach this way. Right-handed shooters can reach and manipulate the controls easily and quickly with their left hand while holding the weapon at the ready with their right hand. Southpaws, however, might prefer the older Eotechs with slightly awkward but ambidextrous rear controls.

We found the controls to be robust and intuitive, and easy to use by touch and in complete darkness. The only exception was the (useless for civilians) ‘NV’ button that toggles the night-vision compatible reticule. Since the NV reticule is invisible, I thought the ‘NV’ button was the on/off switch, until I read it and stopped using it. Problem solved.

What about handling? Eleven ounces is a lot of weight, which can really change the handling characteristics of a rifle. On an AR rifle or carbine, however, the Eotech feels right at home. When the rifle comes up to your shoulder the Eotech’s reticule comes right up to your eye, and the aiming window is so large that your intended target is probably already centered in it.

During our testing, all three of us agreed that the Eotech was the fastest red-dot sight of the three, because of its huge window and conspicuous reticule. Looking through the Eotech’s 30mm x 23mm prism is like watching a widescreen TV with the aiming reticule floating in it.

Head alignment? Doesn’t matter. Sight picture? Fugeddaboutit. Cheek weld? We don’t need no stinkin’ cheek weld! In these regards, the Eotech provides superb shooting ergonomics despite its size and weight.

Adjustments:

Reticule brightness is adjusted by two buttons on the left side of the unit.  The rear button (nearest the shooter’s eye) increases brightness, the forward button dims the reticule, and both buttons together turn the unit on or off.  A third button toggles the ‘Night Vision’ mode for Solid Snake-types with Gen III+ night vision goggles. Unless you are Solid Snake himself, ignore it or buy a cheaper Eotech without NV compatibility.

Point of impact is adjusted by means of two large slot-headed screws on the right side of the unit. Directional arrows are large and easy to read, and the screw slots are big enough you can use a nickel as a screwdriver. Each firm, positive click is advertised as ½ MOA, and once again neither the gun nor the shooters were precise enough to test this claim. It only took a handful of shots to zero the Eotech with our ammo, and once centered it never moved. Good enough for me.

Optics and Reticule:

The Eotech’s optics are exceptionally bright and clear, and the reticule is utterly visible and conspicuous even at low brightness settings.  The prism and coatings do not perceptibly darken the target view, nor do they impart a perceptible tint or hue.

Instead of a simple red dot to aim by, it projects a 65 MOA aiming circle with quadrant ticks (short lines at noon, three, six, and nine o’clock) and a tiny 1 MOA dot in the center.

Only a laser can produce such an elaborate holographic reticule pattern, and lasers use a lot more juice than LED diodes do. In consequence, the Eotech has a battery life of ‘only’ 600 hours of constant use. The XPS-3 can be programmed to turn itself off after a set number of hours, but I don’t know if my test unit was so programmed and I didn’t try to do it myself. It sounds too complicated to me anyway; I’d rather turn it on and take responsibility for turning it off myself. If the battery dies, you can always use one of your spare Streamlight or SureFire weapon light’s CR-123 batteries anyway.

Although the reticule is optically sharp and well-defined, it has a slightly ‘pixellated’ visual appearance, because it is a laser-projected hologram.  Some shooters find this slightly distracting, at least initially, but not so much as to draw their attention away from the target.

Of the Eotech’s 20 visible brightness settings and 10 invisible NV brightness settings, you’ll almost never go above 15 on the visible ones and you’ll never use the NV ones at all. At max brightness, above, the Eotech is easily bright enough to read by, and looking directly into it for extended periods may in fact cause permanent eye damage. It’s insanely bright.

Precision:

The Eotech, mounted on a highly accurate Armalite M-15, produced 50-yard groups which were slightly more than triple the size of groups obtained using out 3-9×40 telescopic sight. The Eotech groups averaged 2.6”, while the 3-9×40 groups averaged 0.79”

I had expected the Eotech to be more precise than the Aimpoint, because the Eotech’s tiny center dot doesn’t occlude as much of the target as the latter’s 3 MOA dot, but I was wrong. Comparing the two scopes across different rifles is comparing apples to oranges, but the Eotech seemed to be demonstrating more of a loss in accuracy when compared to the high-power scope (2.6” vs. 0.79”, a factor of 3.3) than did the Aimpoint (2.05” vs. 0.65”, a factor of 3.15).

I have no explanation for this, other than to note that our trigger time with the Armalite/Eotech combination was cut short by feeding malfunctions. It may be the shooter’s fault: we may not have had time to get used to the gun and shoot our best that day.

A Scope For Cheap Bastards:

For the sake of my cheap and occasionally contrarian nature, I also acquired an off-brand clone of the Aimpoint Micro (this one sold by Primary Arms, Inc. for $89) to see how it stacks up. After all, not all of us can afford $500 or more for a scope for our tactical carbine.  With so little at stake, my reasoning goes, there’s little cause for disappointment if the results are less than stellar.

There are some YouTube videos out there showing Primary Arms scopes surviving dreadful mistreatment, but I didn’t try to replicate them. The Primary arms proved waterproof to the depth of my bathroom sink, and that’s as wet as it will ever get on my watch.

I mounted it on an Ultimak gas-tube rail on my AK-74, for which I’ll eventually pen a warts-and-all review here at TTAG.  The Ultimak is the only scope mount that allows co-witnessing with the AK’s very low iron sights.

The Primary Arms clone and the Aimpoint Micro have very similar specs on paper, but when you set the two scopes next to each other you notice real differences.  The devil, as always, is in the details.

Dimensions:

Dimensionally the Primary Arms is the same length and .2” narrower than the Aimpoint Micro. The Primary Arms brightness adjustment is on top, so it’s a little bit taller. Since my test sample lacks the high-rise QD mount on the Aimpoint tester, the Primary Arms scope is just plain tiny, and weighs only four ounces. It’s so small (and cheap) it could be an excellent choice for a target/plinking .22 pistol or rifle.

Ergonomics and Adjustments:

The Primary Arms controls don’t give you the same easy-yet-precise feel of the Aimpoint’s dials and screws. The top-mounted brightness dial is stiff to turn, and there is no stop at ‘0’ so you can’t turn it off by feel alone.

Once you remove the threaded covers, the Primary Arms adjustment dials are turned by small slotted screws with invisibly tiny arrows showing you which way to turn for up or right. It works fine, as long as you’ve brought your jeweler’s loupe and a small screwdriver into the field with you. The zero has held steady so far, so maybe you’ll never need to adjust it as long as you don’t switch ammo.

In terms of the handling ergonomics of the weapon it’s attached to, the Primary Arms (or an Aimpoint Micro) on an Ultimak gas tube rail does wonders for the handling of an AK-pattern rifle. The AK’s notoriously poor iron sights are rendered irrelevant by the magic floating red dot, and the tiny scope neither bulks out nor weighs down the rifle itself. The Ultimak gas tube rail is outstanding in its own right, which is good since it’s the only credible way to mount low-profile optics on an AK anyway.  AK side rails sit too high for my tastes

Optics and Reticule:

The Primary Arms has pleasantly clear optics for a scope in this price range. The front lens coating looks very very similar to the Aimpoint’s, and they both impart the same color and depth of hue to the target field.

The Primary Arms has a 20mm window like the Aimpoint, but as you could tell from the earlier pictures, the ‘clear aperture’ is somewhat narrower on the Primary Arms. The Aimpoint’s internal LED emitter is securely screwed into place at the 4:30 position to allow low co-witnessing with iron sights, while the Primary Arms LED is held down in the same position by a glob of what is presumably epoxy. It might be just as strong (or then again it might not) but it is neither as precise nor as elegant.

Both scopes feature a 3 MOA dot. Both dots are fairly sharp and well collimated, but the Primary Arms dot is just slightly fuzzier and nowhere near as bright. Just like Nigel Tufnel’s amp, the brightness dial on the Primary Arms red dot goes to eleven.

At this maximum brightness, its dot is only as bright as the Aimpoint is at 10 out of 12. It’s certainly bright enough to be useful on a sunny day outside, but I suspect it would be overwhelmed by the glare of a bright, sunny day in the snow.

The Aimpoint and the Primary Arms both use the same CR-2032 battery, but you will need to turn the Primary Arms off when you’re done shooting it. The battery is a mere mortal in this application, with an advertised lifespan of 20 to 40 days of constant use depending on brightness.

Precision:

My AK-74 is not, I suspect, the ideal platform for testing the precision and repeatability of any optical device, especially since I feed it a monotonous diet of Soviet surplus 7N6 corrosive ammo. It’s a less-refined optic for a less-refined rifle, and thus I haven’t wrung out the Primary Arms the way I tested the Aimpoint/SCAR combination or the Eotech/Armalite combo.

My initial testing suggests that the Primary Arms performs similarly to the Aimpoint in terms of precision and zero retention anyway. That being said, I doubt that the Primary Arms would survive the level of abuse that Aimpoints and Eotechs are designed to shrug off.

Summary:

I have no interest in either starting or wading into a ‘Ford vs. Chevy’ flame war about Eotechs and Aimpoints. They’re both rugged and reliable to the point of near-indestructibility, and they’re both used in large numbers by our armed forces and police. They’re both very costly, and for those who need and can afford them they’re both worth every cent.

The Aimpoint is a lot smaller and lighter, and this makes it a better fit for many rifles and carbines. Their batteries last so long that after two or three new batteries you’ll probably need to replace the rifle the Aimpoint is attached to.

The Eotech seemed to offer slightly quicker targeting, and it may be slightly less precise, but these impressions are tentative and not based on very much data. Regardless, we all loved the Eotech’s huge target window and excellent reticule, which make you feel like you’re playing real-life Call Of Duty but without any of the killing-and-dying bits.

If I had a flattop AR and enough money left over, I’d put an Eotech on it and never look back. They look and shoot like they were made for each other; probably they were.

Eotechs are too tall and bulky for most other rifles, however. They’re far too tall for the STANAG claw mounts on older HK patterns (I’ve experienced this personally) and too tall and thick for mounting on FNs. AKs have very limited scope options, and Eotechs are not among them; they’re just too tall to put on a side rail and too thick to mount on an Ultimak. Since I have an AK, it wears the Aimpoint clone.

And what about that clone? I included it in the comparison just to illustrate what the Aimpoint’s extra money gets you. It gets you a lot. A lot more refinement, a lot more ruggedness, and those magic batteries that you won’t have to replace until the kids are all through college.

The Primary Arms clone is a little clumsy, but it works. You get what you pay for, and sometimes you get a little lucky.The Primary Arms is all glass and metal, it’s actually waterproof, and it holds its zero. It’s a lot more scope for $89 than many Chinese and Russian red-dot knockoffs (and even some ostensibly American brands) at similar or higher price points.

Specifications:

Aimpoint Micro H-1

Price:  $500+
Weight: 3.0 oz bare, 3.7 oz with low mount, 5.8 oz with LaRue QD riser mount (extra $109)
Dimensions: 2.45” long, 1.64” wide, 1.65” from top of rail to the center of window
12 brightness settings
Battery: CR-2032 coin, lasts 5 years constant-on
Waterproof to 15 feet
Co-witness with AR/SCAR, using high-rise mount
Not NV compatible
½ MOA adjustments
3 MOA dot

Eotech XPS-3

Price: $600
Weight: 11.1 oz
Dimensions: 3.6” long, 2.14” wide, 1.68 from top of rail to center of window
20 visible brightness settings, 10 NV brightness settings
Battery: CR-123 (same as most tactical lights), lasts 600 hours at brightness 12
Waterproof to 33 feet
Co-witness with AR using built-in QD mount
NV compatible
65 MOA ring, 1 MOA dot
½ MOA adjustments

Primary Arms ‘Micro Dot’

$89.00
Weight: 4.0 oz with low Allen screw mount
Dimensions: 2.45” long, 1.45” wide, 0.45” from top of rail to center of window
11 brightness settings (Nigel Tufnel Rules!)
Battery: CR-2032 coin, lasts 500-1000 hours
Waterproof to the depth of my bathroom sink
Not NV compatible.
3 MOA dot
Co-witness with AK using Ultimak rail, or with AR/SCAR using optional high-rise mount.