Just wanted to get people's thoughts on wearing a parka in a sleeping bag. Do you think there is enough room to wear a DAS parka inside an Integral Designs North Twin (I'm 5'9" 170#). If not, is it worth sizing up to a wide bag? It would be an extra 10oz for the wide in the same length.

Thanks,
Bob

I dont have experience with either the bag or jacket, but if you are going to get a new bag for use with a parka, get a nunatak bag, you are able to adjust the girth to fit your clothng system. Wider with a jacket, and tighten it up if you are wearing just a base layer. the Arc concept is also great because it will take you to its temp rating all the way up to 60 degrees because you can undoo all the straps and just use as a quilt, but when you are pushing the limits you can tighten them up to an almost closed bag.

the quilt approach is a fine approach for the reasons stated. however, if you're not sure you want to go the quilt route, give the Montbell SuperStretch bags (avail. in ~7 temp ratings in both down & synth, covering -40 deg F up to 50deg F). the extra 10+ inches of girth (~71" at the shoulders) cp. to most mummy bags, provided by the SuperStretch system allow for the type of layering you're considering without restricting movement.

I have a mont bell bag as well, I have not used it with insulating clothing but the elastic in the baffles may still constrict a down jacket?

It will probably not be a problem though, it is a huge bag before stretching the baffles

I recomend both Nunatak and Mont bell

I alread have a Nunatak quilt and I love it for 3 season use but I'm not sold on the idea for winter use.

What does anyone out there think of the Montbell stretch system. Would it be able to stretch without compressing the loft my the jacket inside the bag?

oops.

Edited by kdesign on 01/17/2006 19:45:45 MST.

I've wondered about that---one of the reasons I've never seriously considered their bags. Another being the relatively low fill power of their down compared to other premium bags and quilts.

By the by, Bob--I've now recently used my Nunatak Arc Ghost/Alpinist hybrid down to 15 degrees. In a tent -- MLD bivy, quilt, Micropuff P/O , Lt. capilene baselayer, sleeping on Torso-lite, GG Nightlight pad. Warm and toasty.

I think that with a high loft down jacket the mont bell stretch baffles would be a problem, the bags were designed for comfort, probably for the traditional lightweight backpackers that wear just a baselayer to bed in a warmer bag, not us super ultralighters who bring a lighter "less warm" bag with insulating clothing.

I wish mont bell would use 900 fill power down, they are some of the lighest bags out there but could be much lighter

Kevin, This weekend I used: tent, Arc X, DAS parka, base layer, cloudveil inertia pants, Torsolite, and 3/8" thinlight.

First night it was 15 degrees and there were 2 people in the tent. I was warm most of the night but cold by morning. Next night it was about 25 but it was only me in the tent and I was cold most of the night.

It was the first time I used the Arc X outside of a bivy and I found it drafty. Never found it drafty in the past using a bivy. Maybe the pads were inadequate? Thoughts?

Thanks,
Bob

Could have been the lack of calories?
could have been because you were alone?
Could have been your insulation lost some loft?
could have been any number of things really

also you can always use a bivy inside a tent, as long as it is breathable

I guess that it would depend on the size of the individual. The interior "unstretched" girth ~53" and is only 5"-11" less than other bags. For example, the FeatheredFriends Light Flight series comes in "3-cuts" with should girths of 58", 60", or 64".

Kevin,

Read something maybe a year ago. Can't locate it on the web now, and not even sure whether to believe that it's true. I do, however, have a fairly clear recollection of the salient points of that web page.

The web page was from a sleeping bag manufacturer and stated that fill power measurements can actually be done via different methods, and what the USA calls 850 is called either 725 or 750 (i forget which the article stated) in Europe and the rest of the world.

It also stated that in the typical American marketing strategy that what is now being called 800+, 850, or even 900 is the exact same stuff that, in the USA, used to be called 750 some years ago. It's merely a difference in measuring, not the down. Given a company's penchant for $$$, it's not hard for me to imagine that manufacturers wouldn't want this to be known (if it's true).

Again, i'm NOT sure whether to believe this. However, if it is true, then the Montbell bags (assuming this Japanese company is not using the same measurement standard employed in the USA) might be comparable.

Does anyone else have any input on this? Would really appreciate knowing if this is true, or just another let's slam anything associated with the USA (not that some of the criticism isn't justified).

Your pad arrangement might have been a little skimpy. You could try the thicker Nightlight. Was the quilt wrapped around the pads, on top of the pads?
I did have the extra layer afforded by the bivy, which also helps to perserve loft from tent condensation. There is not a whole lot of down in these quilts and you can quickly lose loft if your bag is subjected to moisture. Any longer or colder a trip than I was on (2 nights), I would have also added my VBL--not only for some added warmth, but to preserve bag loft from body generated moisture.

There simply could be the degree of personal cold acclimitization.

As Ryan points out, there are a lot of possible factors.

PJ, I do remember the discussion. There's a lot of smoke and mirrors in this area. I am only concerned by real world loft/ weight ratios. I can measure a bags loft and I can weigh it. Something tangible as opposed to Industry claims.

I have found comparable bags from Western Mtneering, the Marmot 900 series and Valandre which would indicate at least a similar quality filling, no matter by what standard the fill power is measured by.This is by personal observation, not Manufacturers specs.

KD,

I understand you. Quantification sure beats marketing hype.

My favorite bags are from WM. Their lightest series/bags are cut a tad tight. I don't mind, but some others might.

I've emailed Montbell this past fall. Wanted a colder bag. Narrowed my choices down to two: WM Versalite Super, or a Montbell SuperStretchDownHugger (#1 or #2). Same day, heard back from Nels. He praised the WM bag i mentioned, and spoke highly of Montbell's. Sadly, only one question was not answered as i hoped it would be. I was hoping for a "number". Instead I got "words". Montbell doesn't list a LOFT value for any of their bags, nor could Nels provide any. I find that Montbell makes fine bags, easy to zip/unzip and mine has yet to foul. Unlike my WM, TNF, and WMtn bags - must keep zipper as straight as possible or 1) it's a real "bear" to zip, or 2) it may catch some fabric and snag. Obviously, this happens only when 1) it's really cold out and you want to zipper up as fast as possible so as not to chill, and 2) when you really gots'ta-go and you can't get out. Maybe i should be gettin' me a quilt? It's tough for me to cp. warmth between similar bags that i own as conditions are different each time out.

The other thing i noticed, even assuming the Montbell 725fp down to be rougly equivalent in loft to the WM 850fp down is that (i can use a WM short bag) the down fill in the WM is divided up along 66", but the the Montbell's down is divided up along 70". Obviously, the difference goes the other way if someone can use a 70" bag from Montbell, but another Mfr's regular length is 72". In that case Montbell's down insulates a shorter length. Just some factors to complicate the matter further. However, having said that, perhaps these factors shouldn't even be considered, and please correct me if you feel i'm mistaken, LOFT is really the deciding factor in warmth, now, isn't it.

Another thing to keep in mind when cp. weight related ratios, is that the Montbell SuperStretch system adds 2oz to a bag's weight versus their non-SuperStretch bags. Fill wt. is the same between them however. So, unless i'm mistaken, when wt. related ratios involving Montbell bags are considered for warmth purposes, the non-SuperStretch bag wts. should be used, or ~2oz of wt substracted from the SuperStretch bags. Obviously, if considering "pack" wt, then the 2oz shouldn't be deducted.

"I wish mont bell would use 900 fill power down, they are some of the lighest bags out there but could be much lighter"

This is not nearly the big deal it's made out to be in my opinion. Looking at real numbers, the difference between 850-900 down and the "cheap" 750 down is usually less than 2 ounces for equal loft in a bag with 12 or so ounces of fill. Considering the huge price premium for 900 down, this is probably the worst cost/benefit place in an entire gear list to shave 2 ounces. Taking a leak before donning your pack will save more weight. I know many folks want the absolute best money can buy, but I'll keep the $100 difference in price and put it into other gear that will yield more weight savings or offer better performance. My 2 cents.

Paul
This gives details of the European formula. Now all you need is the equivalent U.S. formula and a calculater. http://www.thebmc.co.uk/safety/advice/articles/issue18_down.pdf

David

I've got a Montbell bag and the down inner jacket. I strongly feel that both need more, and better quality down to work to their potential. When fluffed to their maximum loft, both show significant gaps and thin areas within their fill areas.

Even at consumer prices, down isn't *that* expensive--making the shell has to be the biggest part of the manufacturing cost. IMHO, based on their clever designs they'd be competing with the top echelon if they'd upgrade their insulation.

Curt--never pay full retail. I got my 900 fill bags off of Ebay.

It's true, everyone needs to play out their own particular cost/benefit analysis. That being said, paying a premium for a Nunatak Arc w/ it's quality and versatility was well worth it for my particular needs---
no regrets.

I believe there are longevity issues associated w/ higher and lesser lofting down qualities. I've heard spin on both sides. My observation--- well maintained premium lofting down bags in my possession have been holding up better. There's not a little anecdotal evidence to this effect, also.

Edited by kdesign on 01/18/2006 12:33:02 MST.

I think the 750 fills weight is not the only problem, I have seen that my nunatak bag lofts much faster than my mont bell.

but this may be because 10% of te fill is feathers not down