[at-l] Sleeping bags

[jbullar1 at twcny.rr.com (Jim Bullard)]

At 09:18 PM 10/25/2004 -0500, David A Jones wrote:
>People who know the most about hiking, and sleeping bags in particular, 
>seem to talk about choosing a sleeping bag like it's a matter of choosing 
>which down bag to get.  I also hear a lot of talk about not getting down 
>wet.  I may be completely ignorant, but it seems pretty wet out there to 
>me.  Are there just a lot of people confident that they will not get their 
>down bags wet?  Or does  down actually respond as well to dampness as any 
>other material?  (Actually, I think geese do get wet.)  I don't hear 
>anybody saying "down kills".  Nobody is talking about down like some talk 
>about cotton?  I would think the best bag be the one that is still warm 
>when wet, or the one that will dry most quickly, or at least one that 
>won't self destruct if it gets wet?  I'd use this sort of logic to choose 
>a wool sweater over a cotton sweat shirt.  How does wet logic apply to 
>sleeping bags?   Easy cleaning of a synthetic bag would be a second 
>consideration to me, but still a valuable one.  I just don't get it.  So 
>down is light.  How much more weight are you really lugging when you 
>choose synthetic?  A pound?
>Isn't that extra weight kind of like wet insurance?  Never mind the 
>cruelty thing.

Yes geese get wet but their down doesn't. The down is a fluffy underlayer 
that makes an insulating space between their outer feathers (the part of 
them that gets wet) and their skin. A down bag either uses a DWR material 
on the outside or you can take other steps to keep it from absorbing water, 
i.e. a plastic/silnylon stuff sack when not in use, a tent/tarp when in 
use. If you fall in a river, get careless about how you handle it in bad 
weather, etc., it can get wet and a wet bag does not insulate as well. The 
wetter it gets, the worse job it does of keeping you warm. Synthetic will 
perform somewhat better when wet but dry, the best synthetic bag isn't as 
warm, ounce for ounce, as an equivalent down bag. Synthetic is easier to 
care for.

As for "cotton kills", it is almost impossible to avoid getting clothing 
wet (can't hike inside a tent and you'd still sweat even if you could) and 
wet cotton will wick heat off your body when you stop hiking and generating 
excess body heat. Even putting other dry clothing over a wet tee shirt 
doesn't help. When you stop at the end of the day you need to get dry ASAP. 
Actually some folks like a flannel (read cotton) liner for their sleeping 
bag both to keep the bag clean and for warmth, but you have to keep it dry 
just like you have to keep your down dry. Personally, I'd rather go with 
silk for a bag liner. It's lighter and warmer.

And yes, an extra pound or two can be a significant amount after 18-20 
miles but YMMV.