I was wondering if there is a bag or quilt that compresses more than the others?
Or is the compression size just a function of the amount of down?

What is the smallest volume for a 40degF bag? I saw on one site that the Marmot Plasma 40 packs down to 7"x7" (but this size was not substantiated on a different site). So first, what does it mean when a volume is represented by just 2 parameters? Can we assume the third parameter is necessarily less than or equal to either of the two specified values? I have a Plasma 15 now, and love it. If the plasma 40 really packs that small (7x7), then I'd grab it in a second. Anyone have this bag in particular and can verify the pack size?

Do quilts pack down smaller than bags?

Also, I have the same question for my tent setup. I have a UL Fly Creek II right now, but am thinking of a z-packs hexamid or similar, but only if I can get the pack size down considerable from the Fly creek.

Basically, I want to get the size of these two items down so I can get a smaller pack as well (right now, have the z-packs arc-blast which I love but it is large).

> Do quilts pack down smaller than bags?

Significantly smaller, in my experience. The amount of down matters, but so does the shell material. The thinner the material, the smaller it'll pack down. I'm not sure how small the Marmot Plasma 40 gets.

Yes, you can expect quilts to be less volumous than bags, hence less compressed volume when put into a pack.

I did a study about three years ago on compression that indicated that short term compression (3 days or less) does not hurt a down bag. IFF the bag is fairly dry and not subjected to heat over 120F. Just shake it out really well before getting in.

I have a similar 40F bag that will fit into a xxsmall bag (around 5x7.) This has a lot to do with the shell fabric (Pertex Quantum in my case) as was mentioned. This means that a standard small bag will also hold my down jacket, socks, mid weight long johns and mid weight shirt. All fit into the bottom of a 2012 Murmur in one small sack. I usually use a dry bag/compression bag, a habbit I aquired cannoeing through the ADK's. At the least, I can always expect to sleep dry...at least to start out, anyway.

I have the the golite 1 season synthetic quilt that pac very small uncompressed it is pretty warm it not that expensive if you get it on sale,I picked mine up during time of crazy sales time in Golite's history for $49.00.

I have seen the Snugpac 40 degree synthetic sleeping bags that pack down really small when compressed at army surplus store but are very expensive.

I have seen a few Lafuma sleeping bags 40 degree 650 down sleep bags when compressed in their Lafuma stuff sack at Nomad Venture ad are not that expensive.

I had mountain hardware 32 lamina sleeping bags with the two short zips on each side. It sucked more like a 50 to 60 degree bag that packed down small.Returned after I slept inside my house and it did not keep me warm.So avoided this bag.
Terry

Quilts get rid of the fabric and down underneath your body, so generally they'll pack smaller than a bag. Packability is really a function of quality and amount of down and lightness of the fabric used. For a 40dF sleep system, the temps aren't particularly cold so you should be more than fine with a quilt if you have reservations, vs a normal bag.

Also you can compress down a lot, but the tighter you compress it the more stress you put on the down clusters. Over time this will cause the down to degrade faster than if you pack it looser. So the benefit of a quilt or high quality down product is that for the same weight you don't have to pack as small, so the down stays newer, longer.

For tents, cuben fiber packs up ridiculously small and lends itself well to folding. The following thread has some pictures and eventually measurements of the Zpacks Hexamid as packed. The synopsis is that it's lighter and smaller than a bag of chips!

http://bushwalk.com/forum/viewtopic.php?f=35&t=3935

I purchased a Z packs 40 degree long wide quilt and it packs very small, smaller than my Monbell #3 compacted. Higher rated down fill like 900 should pack smaller than lower rated 650 I would think. I have lots of space at 29L pack for a three day hike with water sources. cannister Stove & pots, food, tarptent, S bag etc.

a quilt will definitely be the most compact option. My katabatic chisos (40 degree, 8.5 oz down) is quite compact. With that and my cuben tarp for three seasons I have trouble even filling my mld burn.

My Enlightened equip 40F quilt packs small if needed.

I put it in a zpacks drybag and roll it down while squeezing. It ends up like 6x6x5 or so, pretty easily.

Way, way smaller than my sons montbell UL 3 , with less effort too. Really about 2/3 the size.