Big Agnes Hahns Peak SL Sleeping Bag: -20 Degree Down - 2008 BCS

I've used this a bunch of nights in anything from the minuses to pretty warm degrees. I have had very good luck with this bag. In the coldest conditions I avoided the bivvy sack and this thing beaded moisture well, kept me dry, and kept me warm! In warmer conditions I unzipped and stayed very comfortable. It is quite a thick bag when it is allowed to air out and can be a little difficult to compress, but it seems to compact pretty well. All in all this is a great back, and well worth the money!

This is a great sleeping bag. I used this in late fall in the White Mountains. The temps got down to around 10 degree. I was only wearing boxer for the night and was comfortable. Ground was frozen and snowed in the morning. I noticed my breathe was frozen on the front of the sleeping bag in the morning. I'm about 5'7" and 150lbs. The regular was a nice fit. I did use the insulted pad from Big Agnes with this which worked perfectly. The bag is light.The only downside was the stuff sack. Not great quality, and I don't believe it would protect it from any moisture. I ended up using my sea to summit compression bag. Also, I had a bit of trouble trying to get it zipped up all the way. It didn't seem like it was stuck on anything.

This thing is warm . . . and light. I took it for a test run last weekend. Temps only got to around 30 degrees. After an hour, I was sweating -- I had to open the side midway through the night. Although a mummy, I had room enough to sleep on my side (I'm 6'1" and 205). All in all, this was a very comfortable bag.

I purposely slept outside my tent to see how the DWR would hold up against some morning frost/dew. Despite the fact that my footprint had small puddles of water, this bag was fine. Only gripe was zipper had a tendency to snag towards the top, but that's true with most sleeping bags.

I'll have to wait until true winter to see the bag's true capabilities, but so far so good.

Not even one night in this bag and my feet were soaked when i woke up I bought one of these for my girlfriend as well and i was up in the middle of the night finding her a blanket just so she would not freeze.. I can not begin to explain how frustrated i was with the quality of this bag I have owned big hahns bags before and they were nice.. but this is an unacceptable bag

Not even one night in this bag and my feet were soaked when i woke up I bought one of these for my girlfriend as well and i was up in the middle of the night finding her a blanket just so she would not freeze.. I can not begin to explain how frustrated i was with the quality of this bag I have owned big hahns bags before and they were nice.. but this is an unacceptable bag

Just went on a 3 night, 3-4 day backpacking/camping trip with this bag. Low temps were 0 degrees 1st night, 2 degrees 2nd night, and -6 degrees (Fahrenheit). I used this with the 2" big agnes two track pad. The first night I went to sleep in a thin base layer and woke up a little cold in the early am but was just adjusting to bag/pad and I think the bag was open a little and I had a little condensation on a very thin base layer top I used. The bag was also spacious, almost too much - I have the long being that the regular is for 5'10" and I am 5'11, plus I wanted extra room for clothing. I threw on a mid fleece and was warm the rest of the night. The next night I filled up the bottom of the bag with all my clothing. I slept with the fleece and was very warm (I had to open the bag some when I went to sleep)and slept like a baby. For whatever reason, on the coldest night(-6 degrees) I was the warmest and had to open the bag and adjust draft collar to keep from sweating. I believe there was a slight learning curve in adjusting the zipper, draft collar and filling the bottom of the bag with clothes so there wasn't so much empty space. I believe I would have been comfortable at the -20 rating and could have done even more if I added more clothing. I should have taken off the fleece because I was starting to sweat at times and I did take off my balaclava but when you're snug in a bag at these temps and wake up to hot - You do not want to lose that heat. With the accompanying two track pad rated at -25 I needed no CCF pad in addition. By the third night condensation had built up on the tent and the bag but the DWR coating kept it from soaking the down and losing loft. However if you are out longer at these temps or colder I would suggest a VBL in addition. I also had plenty of space to sleep on my side and found when I took my balaclava off the third night I could still adjust the hood to give me warmth if needed on my side. All in all a great bag.

Hahns is insane, insanely warm! This is the bag you want for those cold expeditions. The Big Agnes Hahns Peak SL Sleeping Bag is rated down to -20 degrees, and still insanely light. Just be sure to pair Hahns up with the Big Agnes Insulated pad, preferably the Big Agnes Dual Core Sleeping Pad and say auf wiedersehen to to Jack's frosty nightmares.

Reading other reviews, there seems to be a some concern about the pad slot system that Big Agnes uses, and I think it might be justified. There's no down fill on the underside of the bag, which seems like a great idea and certainly trims weight, but without the symbiotic Big Agnes pad designed for this bag, you're probably going to be cold in really low temperatures. I measured and cut a regular closed-cell pad to the dimensions of the bag's pad slot; I didn't really feel like shelling out $100 for a sleeping pad. The advantage of the pad slot system that the bag uses is that you get to carry less pad and you definitely won't roll off of it during the night -- these are both big pluses. However, cold air was leaking in through the sides and bottom of the bag, especially if I moved during the night. I was cold, even though it didn't get below 5 degrees F on my test night. I cut my pad very carefully and there weren't any spaces, so I don't think that this was the problem. It seemed like the bag just wasn't insulating well, though I can't imagine that this would be true with the pad made to go with it. Otherwise the bag is great -- well made, lots of loft, and the draft collar is groovy. I'd recommend getting the accompanying pad if you buy this bag, but personally, I'm going to try a different bag.