Sleeping bag mods at -40 (water, good, light, temperature)

[MissingAll4Seasons]

Granted, most of you don't live in an area where sustained winter temps are well below 0F, but for those of you who do have harsh winters that you might have to survive through I thought I'd share the components of my BOB's "bedroll". Even in a serious compression sack this takes up half my pack, but staying warm and dry (with or without a tent or fire) is absolutely critical. I've used this set-up as a standalone shelter in subarctic winter (down to -60F).

1. Inflatable insulated sleeping pad (like this one) -- not for cushy comfort, you MUST get a thermal break between you and the cold ground/snow, look for one that has an R-value of 5 or more.
2. Mil-Spec Extreme Cold Weather modular sleep system (US GI MSS) -- I've tried other commercial sub-zero bags, but this one can't be beat. It contains a weatherproof exterior bivvy bag, a heavyweight bag, and a lightweight bag that you can layer in different combinations.
3. Radiant "emergency bag" -- a standard mylar one works, or you can splurge for a more comfortable and durable one like the Thermo-Lite 2
4. Thermal bag liner -- you can make one out of micro-fleece material or purchase one premade (like this Reactor)
5. (Optional) Lightweight wicking bag liner -- this is more for comfort and ease of washing, but it does add some warmth. Either poly, wool or silk - NO COTTON/FLANNEL!!!!

Putting it all together from the inside -> out: wicking liner, thermal liner, lightweight bag, radiant bag, heavyweight bag, sleeping pad, bivvy bag. Very important -- for maximum insulation effect the thermal reflective barrier needs to go between the two mummy bags, not on the inside or outside; it reflects up to 80% of your body heat back into the inner bag and any that is lost will still get trapped by the outer bag. Also, note that my sleep pad is inside my weatherproof bivvy bag... it doesn't do much good if it gets wet and frozen... but it can be on the outside if you have a ground cloth.

Two add-on items to extend the shelter would be a heavy-duty ground cloth and a fly/cover. I like the Tyvek ground cloths (http://www.amazon.com/Solo-Tyvek-Ground-Cloth-2-5/dp/B003GLT8JE/ref=sr_1_15?s=sporting-goods&ie=UTF8&qid=1324394361&sr=1-15 - broken link), and the TWing fly, but a regular "blue tarp" would work although it's heavier and harder to pack up tight when it's cold. A tube tent would also work, but it's a little less versatile.

Another important tip... don't sleep with your clothes on, only your thermals if necessary, but definitely no outer wear. Get out of any wet/cold/snowy clothes ASAP because clothes trap the cold just as well as they trap the heat! I normally put my dry clothes in a layer inside my sleeping bag so they are warm in the morning, and use my boots as a pillow/headrest so they don't freeze up solid. Putting on cold/wet clothes and boots when it's extremely cold will only rob your body heat! You're actually safer mostly naked in the elements than you are in wet or frozen clothes.

[wittic]

have you ever BEEN naked in the elements? While it is true that wet clothing quickly robs you of heat, the SWIFT movement likely to be need to save you is QUITE likely to tear the hell out of your skin, in typical terrain, so now you have blood loss and infection problems, on top of your cold problems.

[MissingAll4Seasons]

Originally Posted by wittic

have you ever BEEN naked in the elements? While it is true that wet clothing quickly robs you of heat, the SWIFT movement likely to be need to save you is QUITE likely to tear the hell out of your skin, in typical terrain, so now you have blood loss and infection problems, on top of your cold problems.

Yes, I have been naked in the elements, even in the winter. Your skin likely isn't going to provide enough protection in a full-scale jaunt through rough terrain . Although, I'm not going to waste precious minutes getting fully dressed if my survival is at stake... I have clothes in my BOB that I can put on later once I'm safe if I need to make a rapid exit in just my underwear and boots. I have charged out of my tent in the middle of the night with nothing but my muck boots and a shotgun on more than one occasion... such are the joys of living in bear country

But I wasn't talking about hiking around and having adventures in your birthday suit, what I meant was once you're back at your camp/shelter get out of your cold wet clothes because you will be warmer and safer out of them than in them.

[MTSilvertip]

Excellent post Missing!!

Montana offers the opportunity to try and survive in arctic temperatures too, -40 and worse is not that uncommon, and I agree that Mil Spec bag is an excellent option.

When I was a kid running a trap line, I was not as smart as I am now and didn't have access to a lot of the good quality arctic gear there is out there now, so I made do.
I had a bag I made myself out of 3 layers of wool blankets with some real wool stuffed between the layers, and a canvas cover. Out here we called it a "Soogan". It was surprisingly warm, and surprisingly heavy too! But, it kept the warmth even when wet. I did have a flannel sheet bag on the inside as wool itches to no end

I normally dug a snow cave to sleep in as snow is an excellent insulator. You need a sleeping bench to keep you above the cold air as cold pools at the lowest point. I used fir branches as a mat on the top of the bench to insulate me from the snow. A candle will provide a surprising amount of heat in a snow cave, you just don't want to warm the air to where the snow starts melting, but it is surprising how warm 38 degrees can feel when it is -20 outside.

As I was traveling on snowshoes, I had to be careful not to overheat so I wasn't wearing heavy clothing, but multiple layers of lighter clothing with a wool coat and wool sweater. I could shed as I heated up, or put more on if I cooled down to avoid getting chilled and wet.
I did usually wear long handles insulated underwear which work well as pajamas, and I carried a set of fleece lined moccosins for those quick middle of the night trips
I always wore a wool watch cap too as most of the bodies heat loss is out of your head, and you can sleep in a watch cap.

Yes it was a heavy kit, and when you add the pelts and traps etc. my load was probably pretty close to 200 lbs. But... most arctic or deep cold includes snow, and a toboggan will haul quite a load easily, at least that is what I did.

Extreme cold weather survival is an entirely different skill set than most survivalists will ever need to practice, but it sure doesn't hurt to know how to handle extreme cold conditions.

Knowing how to conserve body heat, build fires, make shelters, and having enough food as your body needs a lot of calories when exposed to severe cold, are all real considerations when you are trying to handle those conditions.

Great thread idea

[MissingAll4Seasons]

I've also snow-caved, as well as running a tarp over the top of a dug out snow pit or a half-wall of stacked brush or cordwood. All excellent "deluxe" cold survival shelters.

I also have slept on top of a bough mattress, but found that the risk of puncturing/ripping my bag was too high. It'll certainly work in a pinch if you don't have a sleeping pad, better than laying right on the ground for sure.

My full bed roll with the ultralight ground cloth and fly weighs in at 22 lbs (now you see why I didn't opt for a regular ply tarp!!). It's not the heaviest thing in my pack (that would be the food & water!), but when you add that to the survival & safety gear and additional clothing, my full personal pack in winter tops out at 62 lbs... slightly more than half my body weight, which is not advisable for someone who isn't used to hiking that much, especially not in the snow. I can pick it up, but I can't actually lift it higher than my waist; so I have to sit down to get into it and then roll-over into a kneeling position to stand up with it. I do have a sled for the heavy gear when we're out on the trapline, ice fishing or getting wood though

[MissingAll4Seasons]

Originally Posted by MTSilvertip

... it is surprising how warm 38 degrees can feel when it is -20 outside.

Yes, I've actually gone into the walk-in meat lockers at our butcher's place just to warm up!

[MissingAll4Seasons]

Originally Posted by MTSilvertip

Extreme cold weather survival is an entirely different skill set than most survivalists will ever need to practice, but it sure doesn't hurt to know how to handle extreme cold conditions.

One historic aspect of the warming climate shifts is hotter summers and harsher winters in areas that would normally be considered 'temperate' -- so it pays to at least have a few concept tips in your pocket just in case even if you do live somewhere warm Besides, you may have to bug-out in a particularly bad winter, or get relocated/travel to a colder region for safety or food, etc.

Even though the cold wasn't normally as brutal as it is up here in AK, I did cut my cold weather survival teeth in PA, NY, CO & WY... so it sure can get cold enough to really suck in many of the L48 states.

I've done my share of extreme heat outdoor excursions in TX & AZ, and extreme humidity in FL & the Carolinas... and those are just as challenging, but for completely different reasons! If I had to chose whether to die from hypothermia or heat exhaustion... I'll take hypothermia hands-down, at least it's peaceful and mostly painless.

[Mac_Muz]

Nice Missing.... Mine varries a little but not much.

Starting from the outside working in:
Gortex Bivey, decent down bag rated to - 10, decent summer bag rated to +40, vappor barrier.
Below the bags, but inside the bivy is a self inflating pad AND a closed cell pad.

I have never been fully naked in -40, but only half, as I get dressed getting out, or getting in the bag system.

Like you, I sleep with my clothing and even my boot shells under my head, or stuffed around my shoulders. I also keep a wide mouth bottle filled with tang in a wool sock in the system. This is risky as you know, but with care I have never had a leak. I prefer to make up the tang really hot, and use it as a bag/ body warmer, but in the morning it's slush.


Back in my day, I needed to run a 35 mm Minolta camera and no one made mittens I could do that job with, so what I did was use very thin glove liners, inside old knee high wool socks with darned or blanket stitched openings for my thumbs and fingers. That much went on before my woolen jack shirt, and were on 24/what ever days I was out, except in the sleeping system.

Last were shells, which are and still are hard to find thin enough, but I have some OR gortex shells that do this well. Leaning how to get fingers in and out with the same hand takes just a short time, and you can vent off too much heat when you need to, with 0 exposure to air. I can pick up dimes, and or open the screw driver blade on a Swiss Knife with all of this on my hands.

The white mountains in NH are not Alaska, but it's as close as I can get.

( thxs for leaving my chasin my tail thread. mac)

[monkeywrenching]

missing, would you mind posting the links you provided in the stickied link thread at the top of the forum. it might be beneficial to others as well in the future.

mw

[GregW]

Before I got stuck in such a harsh environment I would spend the money on a airplane ticket to the Bahamas. Or just find the nearest bar.