My preference for an ultralight sleeping system that will handle occasional unexpectedly cold nights is a 30 F rated mummy-style down sleeping bag with enough girth so I can wear extra clothing inside to extend its warmth when needed. Backpacking Light will publish a series of three articles in spring 2010 covering the insulated components of an ultralight three-season sleeping system for colder temperatures. This review is a separate evaluation of the Sierra Designs Nitro 30 sleeping bag.
When selecting sleeping bags to include in my upcoming state of the market article on ultralight three-season down mummy-style sleeping bags, I at first rejected the Sierra Designs Nitro 30 because it weighs 26 ounces. The lightest bags in this category weigh in at 19 to 23 ounces. Then I noticed that the Nitro 30 (size Regular) contains 12 ounces of down, while the lighter bags contain 10 ounces of similar quality down. That's 20% more, which should translate to more loft and more warmth. The Nitro 30 has some other features that also should contribute to warmth, so how does the slightly heavier Nitro 30 stack up compared to the lightest 30 F (-1 C) rated sleeping bags?
ARTICLE OUTLINE
- Introduction
- Description
- Performance
- Comparisons
- Assessment
- Specifications and Features
# WORDS: 2080
# PHOTOS: 9
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Companion forum thread to:
Sierra Designs Nitro 30 Sleeping Bag Review
Thank you so much for taking the time to do these reviews.
I don't think I'm getting something here. You guys know this stuff much better than I do. So please bare with me as I ask these questions.
So this is a woman's size and it weighs 26oz right?
I'm 6ft1 and usually fit a long. Wouldn't most males of average height or above be better of with a 32oz MH Phantom 15?
Assuming my previous statement is true. Wouldn't a size long in this bag be 2-4oz lighter than my MH Hardwear Phantom 15 or perhaps even the same weight?
You can then make adjustments to your day gear for fast and light and bring a soft shell / shell combo (I use Arc'Teryx layering for my outdoor's needs). Then at night you still have a bag that's rated to 15 comfortably and you don't have to stretch the rating by sleeping all bundled up with layers of down jackets etc.
Thanks!
Looks like this is a Men's Regular bag, not a Women's bag. Most males of average height (at least in the US) would fit in this bag.
The idea behind using clothing to boost the rating of a bag is multi-use. You already have the clothing with you for camp wear so why not sleep in it and carry a lighter bag? The caveat with doing this is you need to know what you need to be safe at expected temps. This includes the bag/quilt and the clothing you use in combination with it. What is necessary varies from person to person.
Hi Alex,
I think part of the confusion arises from the parenthetical Spark 30 reference in one of the photo captions. To clarify, the Spark 30 is the women's version of the Nitro 30.
http://www.sierradesigns.com/p-29-spark-30-womens.aspx
One unobvious factor in the perceived fit of a bag lengthwise is foot size, and the natural angle ones foot assumes when one is lying down. The longer ones feet, and the more they angle downward, the more one feels one is pressing agains the bottom of the bag.
Hey Rick!
I just caught that as I was checking out their site. Not a bad bag. I just feel like my system allows me to go 15 degrees colder without putting on my day gear. All at the price of 4oz. Obviously I can take it down even further if I throw on my layers.
I know all you UL guys are probably thinking Buggs Bunny "what a maroon" when I say that :) but to me I think the 4oz buys a lot of comfort margin in winter camping situations.
One thing to remember is this bag is more stretchy than some. I own a Ul Spiral down hugger #3 (which I use) and the Nitro 30 (Which my Son, Boy Scout uses).
The Nitro can stretch and conform to the user, which I think contributes to its extra warmth on top of the extra Down, but does not stretch as much as my spiral down hugger.
I wanted my son to be comfortable when it gets to freezing or just below without adding insulated clothing (Beyond some Capilene-3), so I went with the nitro because of the extra Down. It is warmer than my Spiral Down Hugger, but I can wear some insulated tops and bottoms (which I didn't want to invest a lot of $$$ in for my son since he is still growing, like a weed)
For my Son the 6 oz lighter (Than the MH Phantom 15) makes a difference, plus I got the bag for $189 on-sale! try thefind dot com to look for deals.
For 32oz 15 degree bags I am looking at the UL down hugger #1
I am debating on getting a Nitro for myself, I love the pad attachment option because I miss my old Big Agnes bag comfort (No rolling off the pad) but Big Agnes bags tend to weigh more than a higher end bag, and their temperature ratings are WAAAY off (IMHO).
Does it stretch at all at the shoulders? Is it a good bag for us wider folks?
Just curious, but IIRC, BPL doesn't like to talk about how warm a particular bag is based on the factors involved, as stated in the review here. I'm actually glad that a bit of reference was provided this time around, though of course it is to be taken with a fair bit of salt.
cheers,
-jim
How will it perform summer?
I owned a Mont-Bell Spiral Down Hugger #3, and got a Nitro 30 for my son (On sale at Moontrail for $189, they are out, but they will carry it again but at $219). I tried the Nitro and found it much warmer than my Spiral DH #3, but it was more cramped. It does have some stretch technology, but it does not stretch as much as the Mont-Bell.
I am about 5' 7" and weigh 220 lbs, so I am pretty wide at the shoulders. If you are a back sleeper, then the Nitro 30 may work for you. but if you are a side or stomach sleeper, forget it. I was barely able to wear a Ibex LS shirt and a Mont-bell Thermawrap jacket in the Nitro. I do wish I had bought 2 at that price, but I sent the Spiral Down Hugger #3 back and ordered a MB UL Super Stretch #2, which should have even more room than the Spiral and be a lot warmer (14 oz Down versus 10 oz), but weighs 9 oz more than the #3 and 3 oz more than the nitro 30.
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