DIY Sub Zero Eotech Test

David of Very Traumatic sent this to us. He decided to test the Eotech recall on his own. He shot his AR with an Eotech and then submerged the Eotech in dry ice to get the Eotech cold enough and test if there is a shift.

Cut to the chase, there is POI shift. David does talk about the variables such as removing the optic and remounting as well as the glass fogging up.

Eotech 2


One aspect I am curious to know is what happens to the rifle when frozen. Will temperature affect POI of the rifle as well?

Nicholas C

Co-Founder of KRISSTALK forums, an owner’s support group and all things KRISS Vector related. Nick found his passion through competitive shooting while living in NY. He participates in USPSA and 3Gun. He loves all things that shoots and flashlights. Really really bright flashlights.

Any questions please email him at


  • Concerned Damage Control Agent

    This issue seems over blown. None of us are high speed death machines operating in the north pole. Besides that AR would give before the sight would.

    Just kidding, LONG LIVE AIMPOINT & AKMs(the AR part was no joke).

    • KestrelBike

      I think the bigger deal is the reported high-temperature POI-shift of 122°F. Car trunk, etc.

    • Henrik Bergdahl

      Where I hunt above the arctic circle -40 is not unusual. That is why I use aimpoint 😉

    • Rick5555

      How is the issue over-blown. It’s know these optics had POI shift at just 32F. There’s many agencies using these optics. In which the weather shifts from 50 to 32 degrees in just hours.

      • Kivaari

        I live where temperatures are often in the low 10s 4 months per year. Right now it is 17.

      • FarmerB

        Just back from a drive down the valley – it’s 23C (73F) in the car, it was 9.5C (49F) where I’m staying and -2C (28F) 20 mins further down the road. And I’m sure an object in the sun in the car would be 30C (85F) plus.

    • John

      >None of us are high speed death machines operating in the north pole

      Except for the native fauna: bears, moose, sharks, walruses and so on.

      And as the Arctic starts melting more, a whole bunch of navies start showing up to party. We’re in an interesting new world, dude.

      • Concerned Damage Control Agent

        When you thought you left the /k/, it turns out the /k/ never left you.

        • Wesley John Blokker

          Dam son! I bet it still shoots though! 😛

  • Mike

    Never mind a POI shift in the sight or even the rifle. If I was shooting in -40 The shivering would effect POI

    • Don Ward

      On my recent trip to Fairbanks, I was assured by the locals that you can’t really feel the difference between minus 10 and minus 40.

      • milesfortis

        I would agree. Once it gets that cold, it simply hurts.

      • Tothe

        As a Minnesotan, I can assure you there is a difference.

        • Bob

          add a little wind to that minus 40 degrees in MN or any where and you WILL feel the difference!!
          Glad I live in AZ now. anything below 80 degrees and I’m cold now!!

          • kiljoy616

            Don’t live in AZ but I conquer with your assessment anything under 80 is a no go for me.

      • kiljoy616

        Good for them but as someone who lived for 30 years of my life up north I can say I sure could feel it. My question I guess is this an issue that even matter if your not in a situation of freezing to death. At least my Eotech has not seen the problem in more realistic temperature like 20 degree. Then again no one is going to catch me out in -40 shooting at anything.

  • bmiller

    Ironically, when you watch Russian IPSC videos, it seems they seem to love Eotechs.

    • KestrelBike

      Russians also put a premium on Miller Genuine Draft.

      • bmiller

        Heck, I guess we could find common ground then.

  • TVOrZ6dw

    I would love to see the same testing done with the weapon also cooled down.

    A book I read by a German Officer that fought through the Russian campaign said their weapons if left out during the coldest nights would not work. His troops had to keep their rifles inside their outer coats until they were needed.

    • Kivaari

      That is a bad way to do it. German and Finn rifles failed early in because they did not de-grease or de-oil the bolts. The Soviets learned that a mixture of 1:1 bore cleaner/gasoline removed the excess lubricants. That way there was nothing to harden. If you take a good prepared rifle and leave it outside it will continue to function properly. Taking a rifle indoors over night (or day) then go outside with it, it will draw moisture. The “sweat” will collect in the bolt and locking recesses. Leaving it outside mean it doesn’t get another chance to collect moisture. You can read that in the Soviet era manual for the M91/30 – M38 – M44. Many years ago the Alaska State Police did a study on about a dozen rifles and found the AK-Galils kept on working. But, a prepared AR15/M16 will work as well. Leaving the rifle outside the tent or cabin is an old-time remedy.

      • Tothe

        Not to mention eliminating the moisture condensation that can rust out things you can’t see.

  • Some of the least controlled non scientific testing I have ever seen.
    1. his control group is 8 moa – that’s terrible.
    2. removed optic and did not re-shoot a group after the optic warmed up which would have been the best way to test without remounting errors.
    3. Shooting 50 yrds why use a magnifier to add more variables? 50 yrd with the Eotech alone should have been easy to accomplish less than 8 MOA.
    4. The POI shift was less than the 8 MOA group size so you have to question the conclusions as presented.

    Personally I would never buy an Eotech even before the problems were revealed but this “test” had so many issues it is inconclusive at best and down right useless at worse.

    BTW I think he needs more rails on his gun, never know when you will run out of space.

    • JumpIf NotZero

      Fair pints, esp on the magnifier. I have no idea what kind of parallax that adds. To someone who isn’t holding a good group at 50y, it seems they may not have an idea of consistent check weld when using optics.

      • Kivaari

        Iron sights should print 1/2 inch groups at 50 yards. The “sight” isn’t very valuable if I can outshoot it with iron. My first EOTech gave me horrible groups, close to 8 inches at 50 yds. I dumped it after getting 1/2 inch groups using BUIS. I thought I must have an eye problem. Then I was convinced, by myself, to try another one. Fortunately I was hospitalized 3 rimes over the summer and couldn’t hit the range. Then the refund offer came to me via TFB, and I sent it in. Now I’d like to know if I’d shoot so bad with the unused new one.

        • iksnilol

          Try an Aimpoint with a 2 MOA dot.


          • Kivaari

            I should have tried the one I had. I put one on an MP5. Tight at the same time I went in for 2 neck surgeries. The first in a series of 5 failed. I retired before I could even zero it. I have a new M4 11.5 SBR. Then 3 more surgeries got in the way of me testing my new EOTech this summer. L lost several months, and the news and refund came along. I’m waiting for the check, it’s in the mail (hopefully).
            I may just leave the M4 with iron sights. I have another 16 inch light weight with a Leupold Mk 4 1.5-5x24mm Magpul pro rear sight and all of them have SSA triggers. Two feet of snow and a mile of unplowed road to get to the benches. I am awaiting the spring thaw.
            Old age and getting hit by a car and losing to two thugs is not good.

          • carlcasino

            Did you supply headstones for the thugs?

    • HKGuns

      Yeah, those DD RIS rails are so uncommon.

      • I think you did not get my humor, then again I laugh at every one that has rails on every square inch of their firearm.

        • Nicholas Chen

          You never know when you might need to grate a lot of cheese.

          • iksnilol

            Perfect when operating in Norway 😛

          • ostiariusalpha

            I don’t think I’ve been secretive about my dislike of quadrails, in fact, I can’t seem to keep it to myself. I sure know that the one thing my RIS grates most (besides the parkerization or anodization off any gun sitting next to it) is my nerves, yet I just can’t see myself getting the peener-palooza SLiM handguard as a replacement. C’mon DD, give me some of that M-Lok magic! Not just for me, but for the children! Which is what I call my guns.

          • Kivaari

            Over the last 10 years I’ve put full rails on two ARs. After 2 weeks, I take them off, and then wonder why I did it two times, since the first time was enough to show me how bad of an idea it is. Now I have
            3 inch 6 O’clock rails, that remain unused. Even those are more than I need.

        • chead

          It’s Daniel Defense’s DDM4V1 rifle that includes an upper receiver with the Daniel Defense M4A1 FSP RIS II rail as specified in the SOPMOD Block 2 kit specification developed by NSWC Crane.

          The SOPMOD Block 2 kit also includes the EOTech 553 as tested, which is why the initial report of POI shift at -/+ extreme temperatures came from NSWC Crane.

        • Bodie

          LOL you laugh at people who have a picatinny rail? You’re acting like he screwed rail sections into his receivers and stock. It’s a freaking picatinny rail.

    • Rick5555

      I agree with your assessment…you’re spot on. Perhaps, the tester isn’t a scientist/engineer. And has no clue how to conduct a proper scientific assessment. Was hard for me to watch, due to the lack of controls. I’m not a researcher per se. However, being a M.D. and watching videos like this, do make me cringe. Just like watching the IV8888 AK video and comparing it to their AR test. The AK barrel was 4150…a carbon barrel. And the AR barrel was Stainless Steel (I believe it was 416R). Stainless barrels heat up faster and don’t dissipate heat as well as a carbon barrel. Oh well, I take those videos for what they are… entertainment purposes only.

    • DaveGinOly

      You’re correct. The proper way to check would have been to remove the optic, chill it, remount it, and shoot it for accuracy. Then shoot for accuracy again after the optic warms up. The test is meant to detect a shift in POI between a chilled optic and a warm optic, not whether the optic will hold its zero after being dismounted and re-mounted (at whatever temperature). The optic’s zero before dismounting is irrelevant.

  • Anomanom

    Not surprising. At -40, one might expect some thermal contraction on the components.

  • Mister Thomas

    I would like to see this test performed on other comparable optics such as Aimpoint.

  • Andy

    Rename the article “Removing and reinstalling your optic can cause POI shift” and it would be more scientific than whatever this 17 minute mess is supposed to be. I’ve had multiple Eotechs fail on me personally, but remove all the other variables in this “test” aside from removing and reinstalling on the rail, and this could also happen with an ACOG, Aimpoint, Elcan, or anything else.

    • Kivaari

      Shove the entire rifle and optic in the freezer. Now that would be interesting. Especially if you could shoot it surrounded by sub-freezing weather. Our county rifle range would be an ideal test site.

  • Dave

    The lawsuit and buy back have nothing to do with removal and reinstall of the optic. L3 settled with th e government and is accepting pretty much all returns. This alone tells you they are admitting that the product is faulty.

    • Rick5555

      The issue is L3 hide this problem for 9 years, knowing about the POI shift. When Eotech believed they discovered a fix for the issue. The attempted to sell the fix as a subsequent upgrade. I have a problem with a company doing those things. It’s called integrity.

  • hking

    Why are people so butthurt about this? L3 FULLY ADMITS there is an issue. Why is everyone running out to do horrible sudo-experiments to test what company fully admits is a problem. Fanboyism or something?

    • I think the method of the testing that in reality does not obtain enough data w/o numerous erroneous variables is what most of us are questioning. Many of us are from scientific or engineering backgrounds and poor test/experiments makes our semi OCD selves go nuts. Many times creating a proper test regime is more difficult than actually doing the test itself.

      • Josh d

        This exactly. I greatly enjoy looking over fail tests when the variables are controlled and recorded.

    • Kivaari

      They lied to our warriors and police. Good guys lives were on the line, and these guys lied.

    • 68Whiskey

      I think it’s worthwhile trying to see if the issues alleged by the Government (and tacitly admitted to by L3) can be replicated by any end user – kind of like how earlier in the year TFB tried to get a HK G36 to shift it’s POI by benching, mag dumping, and benching again.

      Nonetheless I think you and the other commentators are spot-on in regards to the lack of controls. This “test”, as it stands, pretty well proves nothing.

    • carlcasino

      At my age anything under 50 degrees F. and over 105 degrees F puts me at the indoor range. Freon Frostbite to my right (trigger) finger renders it useless in cold weather. Thank goodness for oversized trigger guards.

  • Mystick

    How do you “submerge” an object into another solid object?

    • Rick5555

      Liquid Nitrogen. Science wasn’t your strong suit. You can take dry ice and liquefy it quite easily.

      • Mystick

        Sorry, I don’t take advice from people who don’t know what they are talking about, and add insults to boot. Dry ice is not liquid nitrogen.

      • FarmerB

        And Dry Ice doesn’t turn to liquid naturally (without pressure), it sublimates straight to gas.

    • Kivaari

      It is buried in dry ice, and enveloped with very cold CO2 gas.

  • Carl

    Y’all can hate. I love every EOTech product I’ve ever owned

  • JBC

    I have an eotech 512 on my primary AR. I used one in Iraq and Afghanistan. I suppose my question is how bad is the POI with the temperature change? I have a lot of sentimental and experience with the optic and really don’t want to replace it. If its 2-3 inches at 100 yards i’ll take it, anything over that i’d start to worry.

    • Kivaari

      EOTech admits to 20 inches at 100 yards. 20 inches is a rather significant shift. And it starts at freezing.

  • JQPub

    I’d be more concerned with the shift at high temps, as Kestrel says below (car trunk, sitting in the sun, etc) as has been reported… Removing and re-mounting nullified the results on this test anyway. As for me, I still like Eotech but IMO it’s more suited to ‘police-spec’ than ‘mil-spec’ type uses – which is fine for most of us. Having said that, the one-time (and only one time), mine turned off from recoil, I soured on it a bit for my go-to rifle. It now wears an Aimpoint – and I have 100% confidence in my optic and my rifle feels much lighter these days too 🙂 Eotech is giving full refunds now anyway, so not sure what else they can do. I think that says a lot and should restore trust for any who are put off by the potential shift in zero, or want to slam L3 too much. Just send it in and get your money back and move on.

  • Jay

    To be fair, if you are going to do any kind of serious shooting, in minus forty degrees, would be pretty retarded to bet your life on a rifle zeroed at sixty plus degrees. Optic or not. A lot changes across a hundred degrees difference.

  • Freedoooom

    And not a single trigger reset was heard that day….

  • Ben Wong

    only way to fix this is Iron Sights ! good lord the Marine Corps (when I was in) we shoot 600m with iron sights, granted u practically have to put a tourniquet (sling) on ur arm 10/10 bulls eye is not uncommon

  • Kivaari

    What I found rather pleasantly is EOTech promised to refund my money after completing the on-line form. I shipped mine off Monday last week. It shouldn’t be too long. If they paid the $26 million fine, are giving commercial customers refunds, I can relax a little. That they knowingly sold these to our military and police and around the world is a major moral failure. If good guys died because the sight failed – that is a real problem.

  • sliversimpson

    The best part of any Eotech article is the comments… Everyone is trying to explain why this isn’t a big deal, or how they have always been an Aimpoint fan.

    The truth is that most users wouldn’t have known that the product was faulty is 10 lifetimes of shooting. I own an Eotech and I have shot some excellent groups with it. Now that I know that there is a problem with the optic in extreme scenarios, I will be sending it back and purchasing a different optic.

    The End.

    • Tothe

      Test your specific optic. Find out if it actually affects you. Then use empirical data if it presents itself to request a refund, or keep using it if it works out after all.

  • 360_AD

    Pinky out! very manly and tactical.