Sleeping Bag Temp. Rating

[Speakeasy]

Hi - I have an older synthetic Sierra Designs "Lighten Up" sleeping bag. The problem is that I have no idea what the temperature rating is. The fill weight is 31oz but other than that I have no other info. ANY help would be greatly appreciated.:-?

[Egads]

Google search reveals answer to be an optimistic 20* based no name of bag. However, I noticed the weight of the Lite-n-up bag does not seem to match the weight you have listed in your post.

Reviews
http://www.trailspace.com/gear/sierra-designs/lite-n-up/#description

[Wise Old Owl]

You are going to love this answer, The computers are still averaging your nights in RI as above 32 Degrees, - you don't need to set up a tent, but you need to get your pad, and a piece of plastic to keep the pad clean. I use a cheap weather channel temperature gage as it records the previous nights lowest number and stores it. Go outside and pretend your Backpacking - if you get uncomfortable you might need a new bag. Whats the worst that can happen ? - you get cold come back in.

I am going to guess you have lost some of your loft anyway and most synthetic bags are overrated.

[MileMonster]

I think the Old Owl is right - the only way to be sure is to try it out. First, ratings are a loose science at best. One man's 20* is my 35* because I am a cold sleeper. Sleeping bags lose temp rating as the age, too. If it has been used a fair amount chances are it is nowhere near its original temp rating anyway. The material inside breaks down with use and you don't get the loft it originally had, but you still have to carry the weight. So, if the bag is old and has seen some use, even if you find out what the original rating was it likely will not be accurate. An old, well used 20* might only be good for 40* but you're still carrying the weight of a 20*. Hopefully you can get a ballpark rating of where the bag started its life, but its gonna take a few bag nights to figure out what it is good for now.

[Speakeasy]

Thanks guys - looks like I'm spending a night in the "wilderness. I'll let you know how it turns out ...

[Speakeasy]

This bag has not had much use - the alternative is a kelty synthetic 15 degree bag that must weigh at least 3-4 pounds.

[MileMonster]

Yeah, that's the thing about synthetic bags - they are heavy. I have a down allergy so I'm stuck with synthetic. Montbell uses a hypoallergenic down (washed super well to get the dust out). I'd like try one of their bags to see if it will work for me. It would be nice to carry a 2lb or less 20* bag. Oh well, at least I can worry less about synth getting wet.

- MM.

[Speakeasy]

Well, I did my sleeping back test. It was not too cold but it was very windy. I set up "camp" in my driveway on an uninflated air mattress in shorts and tee. I was warm as toast. Being a native New Englander I doubt I would have bought anything higher than 20 degrees. To be on the safe side I'm going to throw in a silk liner. Thanks again!!