Rethinking down sleeping bags

[Cpl Punishment]

pair a good quality down bag (quality means high fill power) with a bivy if you sleep in the open air. why are you sleeping in the open air? get a tarp!

I'm not, I have tarps. Like I posted earlier, the morning dew we get around here leaves things as wet as a light to moderate rain. I'm not sleeping out in the rain

So the question is, can the repellent finishes deal with heavy dew, or would I need a bivy sack, too?

Oh, and the bags I was looking at say they have 850+ fill -- seems "high".

You perspire all the time. If it evaporates fats enough, you don't notice it.

Perspiration as water vapor turns to liquid water when it gets "cold enough." (As in breathing on Winter-cold window glass.)

When you are in your bag, the colder it is, the more likely the location where it's "cold enough" will be INSIDE the bag.

Yeah, that's why I figure on a 10-15 degree bag. As cold as I've ever seen it here was 25 degrees, so it's not likely to ever get cold enough inside a bag to condense moisture...

My favorite bag right now is an old military ICW bag, that is rated to 15 degrees and is synthetic, but weighs about 8 pounds, which is why I switched to the MSS, which is about 5 pounds with the black bag and bivy sack. I never did actually sweat in the ICW bag, either, even rated as low as it is, so that seems ot be a sweet spot for my environment.

raindog101: thanks for the bivy link.

 

[Ravaillac]

http://www.phdesigns.co.uk/product_info.php?cPath=26_60&products_id=33

I'm using this one.
no frills, not even a side zip, just for insulate and saves weight.

Is it really OK for -13°C???
I think I'm in love.

 

[Hassilov]

So the question is, can the repellent finishes deal with heavy dew, or would I need a bivy sack, too?

Oh, and the bags I was looking at say they have 850+ fill -- seems "high".

Regular DWR finishes: generally no, I wouldn't say they were up to it without a bivy. They wear off too.

But the Gore Windstopper fabric I have no experience with. Sounds like they just covered this bag with material you'd find in a bivy. An all-in-one kinda deal (for winter).

My bags are 575 fill. Good enough for 3 seasons. 850 is real high for 3 seasons IMO.

 

[BlackHills]

So the question is, can the repellent finishes deal with heavy dew, or would I need a bivy sack, too?

I would think that the Windstopper, Epic or eVent shells would have no problem with that but I don't have any first hand experience. If you can find a good place that rents higher end bags near you that might be your best choice, you could try a couple of different models out and see how they handle it before you buy.

Oh, and the bags I was looking at say they have 850+ fill -- seems "high".

It is "high" compared to most bags but WM and FF are the two top makers IMO and I don't think they "stretch" the specs. That higher fill weight is part of the reason they cost more.

Yeah, that's why I figure on a 10-15 degree bag. As cold as I've ever seen it here was 25 degrees, so it's not likely to ever get cold enough inside a bag to condense moisture...

My favorite bag right now is an old military ICW bag, that is rated to 15 degrees and is synthetic, but weighs about 8 pounds, which is why I switched to the MSS, which is about 5 pounds with the black bag and bivy sack. I never did actually sweat in the ICW bag, either, even rated as low as it is, so that seems ot be a sweet spot for my environment..

At those temps I think you'll find you will sweat inside of a 15° WM or FF bag. My experience with synthetic vs. down, especially a higher end down bag, is that the down ratings are much closer to the truth than the synthetic ratings. I have an older FF Swallow that is rated at 30° and I've been comfortable in it at temps below 25°. Conversely, I have a Mtn Hardwear 30° synthetic bag that is cold below 40°.

 

[kgd]

I don't have a windstopper bag, but I'm contemplating getting the MEC windstopper overbag that they sell. I do have a number of windstopper clothing items. They do pretty darn good in light rain and drizzle conditions. The DWR keeps material beaded on the surface and the polyester does not absorb water easily. The chief advantage of windstopper over gortex is its much higher breathability. The double edge sword of waterproofing is condensation from inside. Bivvy sacs are notorious for condensation build-up and given your description of dew, you will like get as much condensation inside a bivvy (venting out to 100% humidity would not help you even if the bivvy has vent holes) as you would dew forming on the outside. My two cents unqualified by experience

 

[Cpl Punishment]

OK, so I'll have to factor that in as well. I didn't know there was such a discrepancy between the temp ratings of synthetic and down bags.

So maybe a 30 degree bag is a better choice?

 

[wildmike]

The 850 down fill allows the bag to do the same insulating job with less fill, which equates to lighter weight and greater compressability. This allows one to carry a better bag in less space in the pack.

Youll save 3-5 lbs. over the weight of your old bags quite a load reduction for 1 piece of gear.

 

[BlackHills]

OK, so I'll have to factor that in as well. I didn't know there was such a discrepancy between the temp ratings of synthetic and down bags.

So maybe a 30 degree bag is a better choice?

It's not so much down vs. synthetic as it is the company. I think the companies that make higher end down bags tend to be more conservative with their ratings and most companies tend to be overstate the ratings. I can only go by my experience but I tend to believe that the WM or FF (and probably the older Marmot bags) ratings are close to accurate and I tend to think most other companies ratings are 5-15° lower than what is actually comfortable regardless of the fill material.

The temp rating is only a guide though, everyone sleeps different so a bag at a certain rating might be comfortable for me at that temp and either too warm or too cold for someone else.

As to what temp rating to buy it's hard to say. If I was buying a bag for your situation I'd probably go with a 30° FF or WM with overfill (which adds to the temp rating). If you could find a place that rents some higher end bags you could get a better idea of what will work for you.

 

[Cpl Punishment]

Yeah, nobody rents squat around where I live.
Oh well, I tend to be a warm sleeper anyway. I've slept in my MSS patrol bag, which is seriously deflated (rated at 30-50 degrees, which I take to mean 50 degrees), down to the high 20s and been warm enough to get a full night's sleep, so a 30 degree bag should be fine.

Been considering this one Kestrel (add the cost for them to do a custom with the eVent covering):
http://www.featheredfriends.com/Picasso/Bags/Product/30Degree.html

Good God, you guys make it easy to spend loads of cash.

 

[BlackHills]

Yeah, nobody rents squat around where I live.
Oh well, I tend to be a warm sleeper anyway. I've slept in my MSS patrol bag, which is seriously deflated (rated at 30-50 degrees, which I take to mean 50 degrees), down to the high 20s and been warm enough to get a full night's sleep, so a 30 degree bag should be fine.

Been considering this one Kestrel (add the cost for them to do a custom with the eVent covering):
http://www.featheredfriends.com/Picasso/Bags/Product/30Degree.html

You should be good to go with a 30° then and that would be a good choice. I'd still consider overfill, they don't list it on the site anymore but IIRC 2 oz only adds around $15 to the price and give you 5 more degrees. I lust after the Winter Wren but it might be too tight for you since you're looking at the wider bags.

Good God, you guys make it easy to spend loads of cash.

That's what we're here for.

 

[Hassilov]

So maybe a 30 degree bag is a better choice?

That sounds like a good all round bag for 3 seasons (maybe too warm in summer though). I know people that use the 850 fill, -30 bags bags for frigid winter camping and a lot of the times they are absolutely sweating.

 

[Runsalone]

Hey CP where do you usually do your camping? Do I remember you saying your in florida?

The rule for sleeping bag temp ratings goes something like this: Under +/-$300 should keep you alive at the temp rate--over +/-$300 should keep you comfortable at the temp rate.

This is a pretty broad generalization but Im sure you can fill in the blanks.

Its a good Idea to get synthetic bags 5*-10* lower than your lowest expected conditions, because of their tendancy to squash and lose thier loft over time. With it goes the temp rating. Down bags (properly maintained) dont have as much problem with this.

BTW from in my experience and from what Ive read about it FF and WM temp ratings are on the money, if not understated just a tad. WM down is also 850+ fill weight. Thier process of getting to that number is a little different than others resulting in even higher quality down than people might suspect. The Fill weight catagorical system is very subjective at best. They say a bit about it on thier site I believe.

Ant intrest in a quilt instead of a traditional bag?

 

[Cpl Punishment]

That sounds like a good all round bag for 3 seasons (maybe too warm in summer though). I know people that use the 850 fill, -30 bags bags for frigid winter camping and a lot of the times they are absolutely sweating.

Hey CP where do you usually do your camping? Do I remember you saying your in florida?

Yes. And in summer, the night only gets to the mid-70s, so I don't use a bag at all. So, 3-season really means one season: late fall through early spring.
I have used the ICW bag up to 60 degrees, and wasn't sweating, but I did wake up having found that I'd unzipped the portion over my chest at some point in the night. But was still warm, but not sweating.

Ant intrest in a quilt instead of a traditional bag?

Not really, but only because when I sleep well, I tend to throw anything off/open in my sleep (even managed to take off a balaclava in my sleep) and wake up freezing. I really need to zip myself in the bag.

 

[redpoint]

Western Mountaineering or Feathered Friends - both make sweet sweet down bags [and they make them in the US too]. I have a 0F rated, EPIC-shelled Feathered Friends bag and it compresses to the size of a basketball. Feathered Friends makes some of the finest bags on the planet IMHO. You really cannot go wrong with down.

1] Yes ... keep it dry. Toss it into a H20-proof Outdoor Research stuffsac.

2] In cold weather, body vapor will condense inside the down. Use a vapor barrier liner [VBL] in cold weather.

3] In the morning, reverse your bag and toss it into the sun to dry-out a bit.

4] Use a bivy if you're going to expose it to wetness: mist, dew, snow caves etc.

5] Try not to breath into the bag while sleeping.

6] If you're just out for a couple of nights, you should be able to keep the down dry with ease. Extended multi-day trips require some dry-out time in the sun. Most high-end bags have black interiors to facilitate this.

7] Store your bag in a large cotton stuff-sac after hanging it up to dry for a couple of days upon your return.

8] These are the exact same steps you'd take with synthetic, but synthetic insulates better when wet b/c it's 'loft' isn't as affected by water.

9] Epic fabric is the way to go ... you want breathability. PTFE membranes keep vapor inside the bag and of course aren't taped at the seams. If you need waterproofness, get a bivy sac.

Down ... if properly cared for, it will last you a long long time, it's totally the way to go for 98% of the time. I have another -12 DegC bag that's still going very strong after 14 years of heavy use. Keeping down dry takes common sense, nothing more.

 

[lambertiana]

i prefer a synthetic bag and just wear some merino wool jammies and possum down socks to sleep in...possibly even a beanie if temps get that cold.

lambertina GREAT pics! oddly enough i almost worked for the parks dept in visalia! are those pics taken in desolation wilderness?

Those two pictures were taken at Upper Golden Trout Lake, in the John Muir Wilderness. It is just north of Kings Canyon NP (the peaks in the background of the first picture are on Glacier Divide, which is the boundary of Kings Canyon NP). I have been in Desolation Wilderness, but I like the high country around Kings Canyon and Sequoia much better (and better than Yosemite, too). That lake is higher than the highest peak around Tahoe or Desolation.