>>1112727I'm sure it would work, but it would be heavy and maybe more work than it's worth.
Look, a sleeping bag can be had new for $40 that is useable in sub freezing temps. You can buy stuff that is lighter or stuff that has better quality, for a price, but temperature is generally not a problem.
Make sure it's large enough and make sure the first (not the second, not the third, only the first counts) value from the EN rating is the coldest temperature you expect.
Check out the pic here:
>>1110657 