Looking at a possible winter set-up of combining a solid 20 degree sleeping bag (15oz of 900pf down) with a Nunatak down balaclava, a Nunatak Skaha down sweater, a pair of Feathered Friends Volant pants and a pair of down booties. The jacket has 5oz of 850+ down and the pants have about 6oz of 850+ down. Is there any rule of thumb to estimate how much below 20 degrees the 11oz of down from the pants and jacket will take me? It will give me, excluding the balaclava and booties, a total of 26oz of down, which seems comparable to some 0 degree I have looked at. Generally, I am 6' tall, 210 pounds, and a warm sleeper. This also assumes a good insulated sleeping mat set-up.
