My -40 Winter Sleeping System

This is my deep cold sleeping system. Coldest I have slept in is -44C and it was no problem. Its routine every winter to spend several nights per winter below -30C and its zero anxiety since the system has proven itself. My buddies use a 2-bag system which is also good if you size them right for maintaining loft. Very important is to use an "oversized" bivy so as not to compress loft, and to allow air to move. Not shown is my head gear which is a loose fitting open face fleece balaclava, loose fleece toque (loose to prevent itchy head), and an ear band around my neck that I can raise over my cold nose if need be, and still breathe without a clammy fabric over my face. I sleep in my day base layer and socks, no need to change, and its easy to get dressed in the morning. I wear my fleece day sweater beyond -10C.

Category:

Travel & Events

Tags:

• Winter
• camping
• trekking
• goose
• down
• sleeping
• bag
• system
• loft
• Mountain
• Hardwear
• Thermarest
• Z-rest
• deep
• cold
• -40
• degrees
• Snowtrekker
• hot
• tent
• boreal
• forest
• fire
• bushcraft

[JHypers]

You may be interested in adding a vapor barrier liner for inside your sleeping bag. They're made out of a non-breathable material with a Mylar backing, and serve two main purposes:

1) Prevent moisture from entering the sleeping bag

2) Boost the bag's temp. rating by reflecting heat back to your body

That should solve your frost dilemma. VBLs extend the life of down bags tremendously, and since you already use a bivy sack, adding this will fully protect your sleeping bag both inside & out.

[Wintertrekker]

@JHypers I have researched the VBL's and yes I agree on what you have stated on their functionality (I have one). My buddy uses one and he likes it. But I don't like the feel of them with the moisture on me, and the hassle of getting in and out. I thrash around as I sleep, and getting up to pee several time a night sometimes (if I over-acheive on hydration :o) means aggravation factor for me. But that's just me. For many people they make the difference for sure.

[coloradomtb1]

Just get a military sleep system...

[Wintertrekker]

@coloradomtb1 JHypers covered it well. I think my system is lighter and just as warm, if not warmer than an equivalent military system. The Z-rest can also be used for other purposes such as a sitting bench if boughs are not available. That MH bag was state of the art when it was made. The outer material "Conduit" finish and which is black, absorbs sun and dries easy if a hot tent is not available. However I just obtained a Canadian Army surplus sleeping hood, which will improve the system.

[brotaque]

Where did sleep in such cold nights? Mountains? Antarctica? -44 C is frozen hell. Now in my town is -22 C and everything is frozed, with normal winter clothes i can't stay to much outdoor, i had to put some of my mountain winter gear. I cannot imagine -44C!

[Wintertrekker]

@brotaque Where? Northern Ontario! Quite normal in midwinter in the far north. Very normal in the old days. Not this winter though. Major warm spell. Coldest I have slept out this winter so far is -28C.  Balmy compared to -40! When you get up at -40, fire is your friend! Fire, either big open fire, or woodstove in a canvas tent is the way to live well in deep cold.

[JHypers]

@Wintertrekker Another option, that I have yet to try, is VBL clothing. I've heard good things from various folks, but for the sleep system it functions the same, only when you get up you aren't immediate shocked by the sub-zero temps hitting a moist body. I guess if you're not down with the clamminess than it probably won't work for you, but it's perhaps worth experimenting with.

[JHypers]

@coloradomtb1 Because.....? His entire sleep system probably weighs less than just the standard cold weather bag the U.S. military puts out. Unless you're talking about the Wiggy's system (which is heavy as it is), the sleep gear they issue is obsolete and overweight.

[brotaque]

@Wintertrekker Ok, thanks for answering.

[Wintertrekker]

@shippen2010 Thank you!