Bivi Sacks, Emergency types & Backpacking types

[Kankujoe]

I did a search on Bivi Sacks and found no threads on this forum.

Anyone have any experience or opinions on the different types of bivi sacks available. Doing web searches I'v found two different types:

1) emergency types (Adventure Medical Kits), this kind is along the lines of a "space blanket" or "heatsheets & a few types are available, some made out of space blanket material, some made out of thermolite material...

2) backpacking types, used to cover your sleeping bag, made out of goretex or some other waterproof/resistent material...

[DOGMAN]

I am a big fan of the backpacker style Bivy bags. I have an OR gore tex bivy that is just like a sore peter (tough to beat)
I cant say enough great things about it. Use it with a Wiggys sleeping bag and a Paco ground pad, and you have the ultimate low profile sleep system. I've used that set-up to 20-30 below zero and was toasty warm and comfy.

About the survival style bivy- they are designed to keep you alive- not keep you comfortable- big difference there.

with all things in life- you get what you pay for

[Sourdough]

Anybody put the bivi sack on the inside of the bag, and not on the outside.......????

[chiye tanka]

Yea, kept me too warm. I was warm all night, but in the morning, I was soaked in sweat.

[crashdive123]

A while back one of the forum members (Klkak) did a "field test" on one of the emergency space blankets. The one he tested did not fare so well. Remember when buying "emergency" gear, it is not all created equal.

[Sourdough]

Yea, kept me too warm. I was warm all night, but in the morning, I was soaked in sweat.

That is the whole point. At sub-freezing temperature night and day your bags gets full of Ice crystals. And you can't get them out. The idea is you can dry your self, and put on dry clothes, but if it is never for the next 4 months going to be above freezing then you can not get the ice out, and every night the ice turns to water, cold water. This is why back in the day when men were men, "REAL" men use bags or as they were called then "Sleeping Robes" made of fur only. That way you can shake the ice out in the morning.

If one wants to learn more study the Idid-a-shoe or Idid-a-bike events.

[Pict]

I have used the guide Gear Bivy extensively in the bush and have nothing but good to say about them. I had originally bought a pair of them to try and they worked great. On a trip home to visit my brother I snagged a pair he had bought and he replaced them. I now am planning to buy four more so I can run larger groups up into the mountains.

My typical set up is a poncho, poncho liner or tropical weight bag, bivy, and paracord. the entire system fits inside a small Alice dry bag/pack liner. I have had ZERO condensation problems with these bags from 18 degrees F up to the mid 70's. The only criticism I have with them are that they are very stuffy if you zip the face screen shut at night. I have slept in heavy bug areas with them and usually end up unzipping part of the face screen to give myself a breathing hole.

I don't know what they sell for but IIRC I paid under $30 for mine. Folded into their little toe pouch they take up a little more room than a tropical weight poncho. IMO this piece of kit is good as gold. Mac

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[Sourdough]

[QUOTE=Pict;85589] I have had ZERO condensation problems with these bags from 18 degrees F up to the mid 70's. The only criticism I have with them are that they are very stuffy if you zip the face screen shut at night. I have slept in heavy bug areas with them and usually end up unzipping part of the face screen to give myself a breathing hole.


It is one thing if it drops to 18*F above at night, and warms above freezing during the day. It is another thing if it never get warmer than -17* F below zero.

[Pict]

I don't get to do any extreme cold weather camping as a rule. On that trip I had a Snug-Pak bag rated to "Extreme 18 degrees" inside the Guide Gear bivy. The bivy has a large top section of black "goretex-like" material that breathes quite well in Brazil temps. I was concerned that maybe there would be some kind of frost issues in below freezing temps.

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This is the shelter we were in that night.

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Interior shot, note the frost on the inside covering the tarp. It was cold enough in there to partially freeze our water in the Platypus bags. I stayed toasty warm all night including my feet so I label that a success. Mac

[DOGMAN]

I do sweat and have condensation in my Bivy and sleeping bag at cold temps when I wake up- however, not so much that it disturbed my slumber though- or that my stuff gets permanetly soaked.

How I dry it out, is when I get up and get moving, I'll hang my bivy and bag over tree branches or the arm of my sled and "freeze dry" it before putting it back in my bag. I'll cook breakfast, take care of the dogs, etc...and then lastly stuff my sleep system.

Right before I put the bivy and sleeping bag away, I'll beat them like a rug with a branch or a ski pole to get the ice off them.

I also always change socks after waking up. My sleep socks are usually damp from sweat, so I don't want to put them straight into boots- so, I put on dry socks and freeze dry my others

This works great for me.

[crashdive123]

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