TFB’s optics guru Timothy Yan recently visited the Alexander Arms facility. He writes …

Temperature and recoil endurance testing of the optic by Alexander Arms. This featuring two of the new Hi-Lux Leatherwood Micro-Max B-Bot mini red-dot sights. The testing rifle is a special short barrel version of the Alexander Arms Ulfberth semi-automatic .338 Lapua Magnum rifle.

The optics and the rifle were frozen for 12 hours at -65° Celsius/-85° Fahrenheit in the cryo-chamber in the Alexander Arms testing facility. After the low temperature test, the gun and optics combo were heated up to +180° Celsius/356° Fahrenheit for the high temperature test. According to Bill Alexander, this high and low temperature range far exceeded what the US military and NATO use in testing their milspec optic. A certain red-dot sight in use by the US military is known to fail at around -30° to -40° Celsius.



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  • simon

    is there any place in the world where military forces would be deployed -10c or colder?

    • Giolli Joker

      Canada, Denmark, Sweden, Russia, USA (Alaska at least), Norway, Finland, many Asian and European mountains…

      • Martin Grønsdal

        I experienced -40C/F twice in my life. In Poland, when I was 5, and in the Norwegian army, 14 years ago.

        I only vaguely remember that temperature in Poland, but in Norway it wasn’t that bad – with no wind it was cold, but dry. I prefer that over -5 and sleet….

    • In Soviet Russia

      Comrade! -10C is of alright, vodka doesn’t freeze!

      • sauerquint

        Take a swig of your vodka after it’s been sitting out. You won’t do that twice.

    • Premek Marek

      The record for NYC is -20 Celsius (January 1994) and in 1985 it was -22 Celsius in Atlanta. Heck, Even in Mexico in 2013 63 out of 67 state municipalities reported temperatures below zero degrees Celsius… January temperatures in Afghanistan regularly fall below -15 Celsius in the hilly regions… So basically almost anywhere in the world.

    • CrossMe

      -10C is nothing even in the not-so-northern parts of europe. In the Mediterranean temps drop to below -15C during the winters.

    • Mountains. There are ski resorts in California.

      • Guest

        that place is called the earth.

    • Martin Grønsdal

      yes. It is called the Earth.

    • MR

      Yeah, they used some oddball “metric” temperature reading to skew the perception of durability of their products. -10C is fairly common.

  • Pete Sheppard

    We’re tripping over the C/F conversion.
    (From earlier posts) -10C is still +14F; brisk. -20C is -4F; still not too cold. I remember -1F in north Georgia, USA.
    -15C equates to 5 above zero in Farenheit.
    In arctic regions, -40C (-40F!) is commonly attained.

  • Mabey.M.

    Its already minus one in southren canada. Last year we went down to minus 30°C where i lived -40°C with the wind chill bad enough for frost bite to set in in 30 mins.

    • Dracon1201

      Hell, we did that for 3 days in Ohio. It sucked. The oil on my hand was sticking to my car door.

      Edit: Sorry, it was -30°F with -40°F Windchill.

      • DougSK

        -40F vs -40 C no difference

  • thedonn007

    So, how well did the red dots perform?

    • Timothy G. Yan

      The repeat freezing and heating broke one of the rear lens cap and killed the battery on one of the two. Otherwise the Hi-Lux mini red-dot sight survived.

      • MR

        They work great when you’re shooting from the hip 😉 IDK, kinda figured an “optics test” would maybe, oh, you know, involve using the optic as an optic.

        • Chase Buchanan

          The optic can’t tell where your eyeball is. It just keeps transmitting light like it’s supposed to.

  • DrewN

    Now that is how you develop a flinch! I hope she’s just posing for show and they fire that beast from a rest of some kind.

    • Timothy G. Yan

      She fired. Notice the burn mark on the table and the wall? There’s a big steel bullet trap right in front of the muzzle. The Ulfberth is actually soft shooting since it’s a semi-auto that weight’s about 25 pounds. I had no problem firing it handheld standing.

      • Timothy G. Yan


  • Paul

    “Brimfrost” 1989. The Tanana Flats near Fairbanks, Alaska got to -89F. Yes you read that right. Dead still air, NOT windchill. I was a squad leader in the 5/9th Infantry at Ft. Wainwright and I couldn’t let my guys outside the tent for more than a couple of minutes at a time. All the SUSV’s in the brigade (except two) froze and just stopped working. Temps would sometimes stay around -50F for days at a time.

  • Jerryjohn

    Is it the aim point that won’t last? Just curious, as I live where we get a couple weeks of -50 C each year

    • Timothy G. Yan

      Probably only the early M68 has that problem. You will be fine with the current CompM4 and Micro T1/T2.

    • MR

      Not sure that that really matters, the lenses look pretty frosty and I don’t have an ice scraper that small. 😉

      • Timothy G. Yan

        Could still see through the lens and the bright dot.

  • dp

    What! AA building .338 gun? What market is it for;military?

    • Timothy G. Yan

      Not a cheap gun and it has a wait list. To get it.

      • dp

        “Its mechanism is based on the Russian DP 28 machine gun.”

        Where is ‘innovation’…..? I cannot believe it. It is locked into receiver thru flaps. There goes the weight my friends. I’d not pay a penny for it. The name is fancy though, as usual.

  • Don Ward

    I guess it’s easier to maintain proper cheek weld when the weapon is -20 degrees F.

  • Rusty Shackleford

    The AA Ulfberht is an absolute beast.

  • GuruofGuns

    I sho would like to know something about the RDS, nice looking at pics and all but how about the sight? Hi-Lux is not a name I associate with quality but I’m willing to learn.

  • markgreenman

    Has anyone used this red dot? I’m debating between it and a primary arms MD-ADS, as they are comparably priced. It’s for a x39

    • Timothy G. Yan

      I am working on a review for TFB. The Hi-Lux cost a bit more but you get:

      – spring loaded flip-up front and rear lens caps
      – tethered turret caps
      – honeycomb lens filter
      – T1 mounting screw pattern
      – storage on the battery cap for a spare battery
      – 55,000 hour battery life

      Btw, we put it on the IWI ACE in 7.62×39 and the Negev belt-fed light machine gun during the Big 3 Media Event:

      • markgreenman

        Thanks Timothy, I think I’m going to go with the Hi-Lux now.

  • ghost

    Looks cool………..