Question about sleeping bags

12:02 p.m. on September 25, 2013 (EDT)
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I have used one bag every season for all my backpacking life. But this winter I want to camp in possible below 20 degree temps. My question is: I have 2 sleeping bags one a rectangular bag I use in summer and the other a mummy I use in the winters, the larger one is rated to 40 degree's, while the mummy is rated at 20 degree's. If I put the larger one over the mummy will the temp range increase, making them together warmer in colder weather? Both are synthetic.

11:23 p.m. on September 26, 2013 (EDT)
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Short answer is yes.  We use this with our scouts.  As long as you don't overly compress the insulation in either bag, you should be able to stay warm.  Of course, make sure that you have a decent pad underneath you.

12:05 a.m. on September 27, 2013 (EDT)
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I always use a pad and now have two my 28 year old ensolite pad and a new Big Agnes inflatable one. I haven't winter camped in more than 30 years where it snowed. I am looking into a 0 degree bag now tho.

12:50 p.m. on September 27, 2013 (EDT)
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Gary you might want to use your inflatable pad over a close cell foam pad, the foam will act as a thermal break from the ground to you.  I would also take along a thermal blanket or bivi ( the Sol ones are good) putting both your bags in this if it's too cold.  It will help a lot with warmth and any wind.  You way have ice or water on the inside of it in the morning but with two synthetic bags you should be fine.  Of course this is not going to be a light system!  And make sure things dry out each day. 

Keep safe!

2:13 p.m. on September 27, 2013 (EDT)
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Gary...keep an eye out on steepncheap. Can really save some do re mi there. I got a big Agnes zero there for $123 that kept me toasty at Everest!

4:02 p.m. on September 27, 2013 (EDT)
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Gary...if you plan to camp for more than a few days in temps 20 degrees below freezing you will need a way to dry your bags out or prevent moisture from freezing in your bags. A bivy will help...but in temps 20 degrees below freezing ice-crystals from your body's perspiration will form in your outer bag...the inside of your bivy...and possibly even your inner bag. I have never camped in that low of temps without the use of a small titanium wood-burning stove (i.e. hot-tenting) which allowed me to dry things while the stove is operating during the day. I do however know people who have backpacked in temps that low...and in addition to using a layered-bag approach and a bivy they either planned to run into town and use a dryer every few days...or used a vapor-barrier (a lightweight rain-suit of the 2.5 variety sprayed with a DWR to keep the suit from breathing).

3:18 a.m. on September 28, 2013 (EDT)
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Last time i winter camped was in Yosemite from January to May 1980. I backpacked into the high Sierra and had a -30 EMS bag. I am looking to get at least a 0 degree down sleeping bag and saving my other spring,summer/fall temp bags for those seasons.

I have a tent the Golite Shangri-la 5. I also have a tarp I have used as a bivy by laying half of it on the ground and the other half over me in places like the bottom of the Grand Canyon where its cold but rarely snows to up in the mountains near Flagstaff  in the winter where snow fall does happen. I have awoke to being covered in 6 inches of snow on the tarp cover.

Thanks for the SteepnCheap idea Giftogab. Hope your narrows hike goes well. I and a friend are hiking the West Rim from Lava Point to the Grotto on either the 8th of 9th of October as a long 14 mile day hike.

In mid October after it slows down at work, I plan to start working 3-4 days a week and taking the other 3-4 days off to backpack and camp out in the GSNM and East Zion from then to April when work picks up again.

3:41 a.m. on September 28, 2013 (EDT)
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I see a lot of bags, down and 0 degree weigh about 3-almost 4 lbs. Is this normal? I do not want to spend lots of money so I guess like this Kelty Cosmic 0 degree bag at 3.14 lbs is average? This one is $170 at Campmor.


I want to be warm and weight is not so much a factor as I only plan to camp 3-4 nights a week this winter and most of my gear is light too. My tent the Shangri-la 5 weighs 5.12 lbs the heaviest item in my gear. With food,water and gear I figure 20 lbs for 3-4 days max, I may do just some overnighters also depending on distance from home. I will bike to the trailheads then hike/backpack in within 20+/- miles each way.

7:56 a.m. on September 28, 2013 (EDT)
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if you plan to camp 3-4 nights per week, multiple weeks this winter, i strongly recommend using something to keep the bag (whether you double the bags or get the zero degree bag) clean.  any kind of sleeping bag liner will accomplish that.  otherwise, over time, oils from your body will work their way into the insulation and start to compromise its effectiveness.  it is much easier to throw a liner into the laundry than clean a sleeping bag.

someone above raised the issue of vapor barriers.  this is what they are talking about:

a vapor barrier is a bag liner that not only keeps your bag clean from body oils, it also keeps all your perspiration at night out of the insulation of the bag.  hence, water vapor your body emits at night can't get into the insulation and freeze.  over a short haul trip, a few days, this isn't a terribly important issue unless you tend to sleep 'hot' and sweat a lot.  over a longer trip, if your bag never has an opportunity to warm up and air out, ice crystals that form in the outer reaches of the insulation, away from your body, can compromise your sleeping bag's insulation.  very easy, back in civilization, to clean a vapor barrier and let it drip dry over a few days.  

on the downside, sleeping in a vapor barrier is an acquired taste.  initially, it feels damp and uncomfortable.  almost necessitates sleeping in wicking long johns for me.  it's not unlike sleeping in a plastic bag.  but, it does work, both in keeping moisture out of your bag and in helping you stay warm.  has been a while since i took a weeklong or more trip in the winter, but i would use one for a trip of that length.  

5:37 p.m. on September 28, 2013 (EDT)
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When I camped in Yosemite Jan-May 1980 I usually used a sheet sewn together on the long side and one end as a bag liner. And even then I aired out my bag everyday. 

10:14 p.m. on September 28, 2013 (EDT)
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I decided to go with the Kelty Cosmic 0 degree bag. I got it for $168 from Campmor.

1:55 p.m. on September 29, 2013 (EDT)
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I have always liked the multiple bag and blanket system for winter conditions. It is not so handy for backpacking, but I rarely sleep in temps under say 10-15 degrees even when skiing. For hunting it can be below zero but usually the transport is by truck or mules.

A really warm bag is a great thing to have, say 0 to -20 degrees, but they don't get used much. I used to watch my friend sweat a lot in his 0 Holubar bag that he made from a kit. If you can manage 2 bags when traveling by bike it is an advantage to have the versatility. Give some thought to keeping the overbag in place. Maybe some large safety pins or clothes pins.

6:17 p.m. on September 29, 2013 (EDT)
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I used to use a wool army surplus blanket sewn with a light rope around the long edges (when folded in half) and one end, then pulled it over my 20 degree bag in the winter in the Grand Canyon where winters below the rims are mild compared to on the rims.

I have also done the same thing with a tarp using twist ties to tie the grommet holes together after folding a 5x8 foot tarp in half longways. Makes a good simple wet weather protector for my sleeping bag And I put my sleeping pad inside with my sleeping bag.

7:24 p.m. on September 29, 2013 (EDT)
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you won't be disappointed with the Kelty cosmic, IMO they are the best budget down bags out there

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