I have read with interest all the good advice on sleeping bags and how to stay warm in very cold weather. Most of the writers speak about a specific area they lived in, or traveled in, as a basis for the post. There is a lot of good, sound advice out there by these writers. I thought I might contribute my own personal opinion as well, since my own experience ranges pretty much across all weather extremes, and was under conditions far harsher than hiking, camping or hunting – at least for the most part. I spent 29+ years in the US Army (mainly airborne and air assault infantry and a short time in the ALARNG SF). My duties took me to many countries and I have slept out in the weather of countries like Honduras, southern USA, Iraq, Kuwait, Saudi Arabia, Germany, Italy and Norway to name just a few. I have experienced quite a range of temperatures and environmental conditions over the years. In all these areas, I had to sleep with what I could carry on my back using a large Army issue ALICE pack and my time out in these conditions varied from a couple of days to over a month at a time. I also didn’t have the option of going in if the weather was bad, the Army tends to frown on that for the most part. My sleeping varied from leaning up against my ALICE pack with a poncho thrown over me to setting up for good sleep around an airfield waiting for a ride home (which, if you know about redeployment then you know that the Army gets you there in a hurry, but can be slow to get you an aircraft to get home). In some of these places I had the use of a HMMWV, but that was the rare exception, rather than the rule. I want to focus on sleeping out in harsh conditions with only what you carry on your back – that is a far different proposition for most folks. Even if you have a vehicle, if it breaks down or you have to dismount and leave the vehicle, you then only have what you can carry on your back.
My personal ideal sleeping setup consists of a hot weather and cold weather system, with both using a common sleeping bag as the base system. While I know some people don’t care for them, I have never found a better base sleeping bag system than the current military issue system (you can buy these used from Coleman’ surplus). It consists of a Gore-Tex bivy sack, heavy sleeping bag, light sleeping bag, and a compression sack. I have three of these I bought as I PCS’d from various units. The old down military sleeping bag was just too heavy and was not suited for wide ranging weather conditions, and I for one applaud the Army for replacing it with the current issue system. Also for my base system I add an old heavy duty Army poncho (pre-dates the current rip stop nylon type of poncho), a dozen bungee cords and tent stakes, and a cut up foam pad for insulation from the ground. The bungee cords wrap around the frame of my ALICE pack against my back and the foam pad fits under it, so no space is wasted on these extras and the weight is negligible. Yes, my old ALICE pack is still my go to pack for my use. Old habits die hard. The bungee cords, tent stakes and poncho make a great lightweight shelter and windbreak for one person and you can put you head on the kidney pad of the ALICE for a pillow so that your pack stays dry under the poncho as well. Many configurations are possible with this setup and you need to experiment on what works best for you. My favorite go-to setup is my poncho strung between two trees in an A configuration. Don’t forget to tie off the poncho hood so that water doesn’t drip in from that opening. The bungee cord allows for quick set up and tear down, even in the dark with no lights and under noise discipline conditions. Yes, the Gore-Tex bivy sack is waterproof and I have just rolled it out and slept in it in the rain, but if you have the time, putting a poncho over your bag keeps it dry so when you stow it the rest of your gear doesn’t get wet (the poncho can go under the straps on the outside even if wet), and it gives you a dry spot to get your boots on and eat chow, etc.