great link, loving it, thank you clearwater

Without seeing the specifics, my only thoughts are to ensure you roll the mats as tightly as possible and then to use cordage to rig up your own attachment method.

Wish had some extra time to post some pics, but DW had a blood clot removed from her leg after thanksgiving, so I am having to do a ton of housework to get ready for company coming in for christmas, and hoping i can make a quick batch of charcloth for some tinder kits I am making for all the scouts and adult leaders as christmas presents. As soon as I have time, I'll see what I can rig up and take some photos to post here.

A word of caution on the temperature ratings specified by US retailers.

Here is an example of the specification for a high spec synthetic Bag - Thermarest Centari™ bag.

http://www.cascadedesigns.com/therm-a-rest/sleeping-bags/centari-0-sleeping-bag/product

The EN Comfort rating is -5 C / 23 F

Yet the Rating given by most retailers regard it as a -18 C / 0F bag.

If you are going to go out in dangerously cold temperatures please go by the EN Comfort rating to give yourself a safety margin and insure the insulation under your sleeping bag has a R rating of at least 4.5 when using a synthetic sleeping bag.

exactly AFLM

the whole idea behind a 0 degree F bag is to be comfortable in the most likely extreme of cold we will encounter. It is doubtful we will venture out in anything colder than the nights we encountered in our recent campouts, 20 to 25 degrees F at the worst, a 0 degree F bag should keep us cozy and comfy in those temps and provide a margin of error and a modicum of safety and comfort in case of any unforseen circumstances.

Besides, a 0 degree mummy bag is what DS asked for for scouting, and if his grades are good this 9 weeks I'd like to reward him with one.

Unless you are tough like the russian climbers who just flake out their rope for use as a mat.

It also depends quite a lot on what clothing you wear inside the bag. Ed Viesturs describes in one of books using a very light bag on Mt Everest. He wears his full body down climbing suit inside a light bag. He does anything he can to save a few grams of weight.

For those who don't follow climbing, Viesturs is the first American to climb all 14 of the 8000 meter peaks, and the fifth person to do so without using bottled oxygen. He has climbe Mt Everest seven times. He is one very hard dude who has spent a lot of time in extreme cold. Don't try this at home, kids.

IMHO - most people buy too much bag; if you are truly camping in 0º weather, then yes get that bag. But most people don't. If you camp at 40º, don't get a 20º bag "just in case."

There is a new system of temp ratings...and it includes comfort, discomfort and "survival" temps.

I tend to agree, I know I'd be way too uncomfortable in a -20 C bag in most conditions assuming I had a good mattress/mattress system. However, its also a personal thing, my kids seem to do just fine in bags rated much lower than the actual conditions.

Actually, as an interesting aside, I used to camp even in the summer with my -7 bag and a low-quality mattress (I didn't do any winter camping back then). When I finally got a good mattress (R value of around 3.5) I found I was routinely too warm. Ultimately I ended up getting a +5 summer bag that I now use unless the overnight temp is actually forecasted to drop below that. I've found the same with my winter set up, unless it is really going to drop below -10 or so the full-blown bag + overbag can get too warm. On the flip side, if the temp is going below what I am equipped for bag wise, extra (dry) layers can help fill the gap (in one case, even partially zipping my down jacket around my bag was helpful).

Well said.

Viesturs is also, IIRC, a veterinarian and a pretty devoted husband/dad who co-authors good books about climbing, and avoids the tendency to trash other climbers. Likeable sort, unlike many of the climber-authors.