Optics in arctic weather conditions?

**Titan74** · 01-01-15, 13:09

How the current rifle optics work in cold winter weather condions? I'm thinking about optics like Aimpoints, ACOGs or small variable scopes and extended field use in cold winter or arctic weather conditions (-30 to +40F, including snow, ice, wet snow and rain).

How the sights take the cold weather, are there issues with freezing switches or batteries that die quickly? How long can you expect the batteries in an Aimpoint (1/3N or AA) or Aimpoint Micro (CR2032) to last in winter conditions? Is an ACOG the most reliable sight if you want to have an illuminated reticle in extreme cold weather?
How to avoid getting snow or ice on to your lenses? Flip caps are probably a good idea but you can't keep them closed all the time.
Eventually you'll get snow into the lenses: are there good and fast ways to get it out (brushes and microfibre cloth come to mind) or is a QD mount necessary so that you can quickly transition from optic to irons? I'd guess that it would be rather easy to get the snow out from the Aimpoints and very difficult to get it out from small variables where the objective lens is usually recessed rather deep in the sight tube.
Any other ideas or experiences regarding the use of rifle optics in winter weather?

**Failure2Stop** · 01-01-15, 14:17

Have a QD mount and a good set of irons, or a set of good offset iron sights.

The biggest issue is lens obscuration, everything else is minutia.

**mcnabb100** · 01-03-15, 02:46

I haven't seen any problems with my ACOG in cold weather. I imagine to remove snow you could just blow it off. If you are super worried about it put your optic on a QD mount.

I guess a worst case would be if you ran a variable zoom and your zoom control or something froze up. Would be especially bad if it froze at like, 24X mag or something. Probably wouldn't happen.

Full disclosure: I haven't really shot in the cold a ton.

**WS6** · 01-03-15, 04:13

Originally Posted by Failure2Stop

Have a QD mount and a good set of irons, or a set of good offset iron sights.

The biggest issue is lens obscuration, everything else is minutia.

I would think that larue would be THE mount for this, no?

**Titan74** · 01-03-15, 05:35

Originally Posted by mcnabb100

I imagine to remove snow you could just blow it off.

This comes to mind first but it is something that you should never do: blowing warm and humid air to cold lenses is the fastest way to cover them with ice (or heavy fog if you are lucky and temperature is above freezing point).

QD mount is a very good idea. Operating small and stiff levers (as with Larue) in very cold weather can still be a chore because of reduced dexterity of fingers.

**WS6** · 01-03-15, 06:08

Originally Posted by Titan74

This comes to mind first but it is something that you should never do: blowing warm and humid air to cold lenses is the fastest way to cover them with ice (or heavy fog if you are lucky and temperature is above freezing point).

QD mount is a very good idea. Operating small and stiff levers (as with Larue) in very cold weather can still be a chore because of reduced dexterity of fingers.

What better option for qd exists for arctic conditions?

**Jippo** · 01-03-15, 07:10

Originally Posted by WS6

What better option for qd exists for arctic conditions?

For instance ERA-TAC makes an easy to grip mount. They are excellent. But regardless of the brand, I agree QD is a must.

Snow is one thing that can block your sights, but the worst is IMHO frosting. As mentioned, even though blowing is a sound method for clearing snow from the iron sights, I'm sure you'll only try it once with your optic. When the glass is a lot below freezing point, it only takes one careless exhale and your optics is blocked. That happens very easily when getting into a firing position. I had once ACOG freeze only from sweat on combat drill as I had to cradle the rifle against my body when changing positions. Codensation on sub-zero glass means instant freezing. And I think the only way to get that off is wiping it with a piece of cloth etc. and the warmth of your hands.