Some sleeping bag/blanket ideas to use with....

[maxwellbest]

Have a goretex British Army Bivvy bag, really good bit of kit, lightweight, etc. Was thinking about using it along with something else as a light weight sleeping system? for use in Summer/Spring walking. Should mention I own a 3 season bag that has always been adequate, with extra layers on even in the snow. Summer, high country such as Barrington tops, any one recommend a light weight sleeping bag or some form of blanket that could be used in conjunction with the bivvy bag plus sleeping mat, thermarest? The 3 season bag is just overkill for a lot situations outside of winter/autumn here in NSW. Or just get into some thermals, jump into the bivvy bag inside the tent and be done with it? Trying to prune some weight/bulk at the end of the day.

[andrewbish]

Consider getting a Summer-weight quilt. Not too expensive to buy. Or quite easy to make ( have a look in the MYOG sub forum)

[Franco]

Max
That does not sound right to me.
First bivvy bags have become somewhat popular with hikers of late but were really made for climbers and or for polar weather.
That is because they tend to trap a lot of condensation giving you a small and wet environment to wiggle inside it.
PTFE (GoreTex and eVent) works well at below freezing because they need temperature differential to push the perspiration outside the shell.
The less the difference is and the less it will work.
Same reason why wearing PTFE on a warm tropical weather is a waste of time.

Some now also like the idea of a bivvy bag with a tarp.
Problem with that (in my mind...) is that you still need a groundsheet, need to be extra careful about location and if insects are about or you have wind driven rain they don't work all that well either.
That I saw again last week when guys that had that combo spent the night inside the refuge whilst I was happily snoring inside my tent.

But if you want to try I would go with a light synthetic quilt.
However your bivvy bag plus a light quilt will still be heavier than a light 3 season bag.
Franco

[maxwellbest]

Making sense there Franco. I guess the quest continues to shave that weight from ones pack. Thanks for your replies.

[Franco]

It does not mean that I am right, right is what works for you.
generally an easy way to go lighter is to think layering and multifunction.
At the same time each function in the multi bit should work.
For example I don't like poncho tarps simply because a poncho is a pita in the wind or off trail and you get wet putting your shelter up and taking it down.
For my sleep system I changed to a lighter bag and started to wear camp clothing. Below zero that is my puffy jacket and pants. (wool hat and gloves if needed)
The total weight in bed (bag plus clothing) is slightly higher than a beefier bag but of course I wear the clothing before I go to bed too...
(nice when you can just get up and go to have a pee without having to ponder for half an hour if it is worth getting dress or not...)
I dropped my "camp shoes" and use plastic bags.
So I take my wet/dirty socks off at camp, wash (or wipe) my feet , put some thin Coolmax on (my night socks) put the plastic bags on top , add the dirty socks and wear your wet dirty shoes undone.
(BTW, I usually have a full wipe down. You (one does...)sleep warmer when clean.
I only re-hydrate meals. so with half an ounce of metho I boil water , add that to my food inside a vacuum type plastic bag , seal that , shove it on top of something insulated and cover that with my jumper or slelping bag. 20 min later my meal is ready in the meantime I often have some soup.
(so my SB/clothing becomes my cozy/fuel replacement)
I only carry a small Opinel knife and a long Ti spoon. That can be a peg too if I lose/break one. (I have a Derma blade in my emergency kit)

Anyway, just some ideas...
Franco

[JohnM]

With the advent of ultralight bug proof tents like tarp tent and Z-packs and others, I really don't see the benefits of the tarp/bivy setup now.

Although going gnarly and super minimalist is fun, mozzies most definitely are not. UL tents are an absolute godsend to hikers.

[Ticklebelly]

Looking for ideas to lose some weight in the sleeping bag department, I started by spending a night in the yard on a stretcher to test out trakkie daks, double socks, thermal top, and fleece vest. Overnight got down to 15 and about 3 in the morning I was looking for something light to put around my shoulders. Upshot was that on a recent 3 nighter, I still took the lightest bag (warmth wise and weight wise) but left the trakkies at home. Overnight temps on this latest were 17-18 and no wind because I camped in deep bush. Lay on the mat all night and only pulled the flap down in the early morning. The experience got me thinking again, so...........

Off to Spotlight and got 2100mm of 210gsm Polafleece. Nice redish colour and a teddy bear motif will get me in good with the ladies, I'm sure. Resdident expert has used her $1,000,000 sewing machine to seal the bottom (each side to the middle) and close the first 300mm from the bottom. Used quilt style, I slide the mat into the footpocket and pull the rest up over the body as required. Spent the night outside in really light weight pants, one pair of socks, and a tee shirt. Min was about 17 and I did take the socks off early in the night. This was on a stretcher and under a mossie net. I figure the tent would add a couple of degrees of comfort (think sleeping bag ratings). I will only take the fleece bag next trip with predicted warm minimums, and will have a extra pair of socks, a merino, a fleece vest, and the rain jacket as expansion opportunities. `Not quite ready to leave the current tent for something like a Tarp tent Contrail (although I do want one) and don't really like the bivvy bag idea but I feel pretty safe with the idea of reducing weight with the light weight fleece quilt as long as some emergency extras are available. I have been in the Barringtons in summer, trout fishing, and those storms can come in quick and COLD.

Weight saving - I knocked 200mm off the width of the Polafleece (finished width 1700mm) and turned the top 75mm for a finished length of 1900mm. Comes in about 600grams on the dodgy kitchen scales (give or take about 50grams). Stuffs very well and I will need to make a custom sack to get maximum smallness, but stuffed size will be about 40% of my light sleeping bag and save 800grams on that bag's weight as well. I am seriously getting down to a sub 7kg pack, before water, for an overnighter.

Also have had the thought that I could use this thing as an over bag in the cold to squeeze an extra couple of degrees out of the proper sleeping bag.

Ticklebelly

[JohnM]

Nice work!

But for under 600grams, you can get an off-the-shelf WM Summerlite sleeping bag that's good to 0 celcius. Kept me warm recently up on the high plains when overnight temp dropped to about -2. Packs nice and small too.

Admittedly your MOYG fleece bag would be a fair bit cheaper than the Summerlite though!

[Ticklebelly]

...... you can get an off-the-shelf WM Summerlite sleeping bag that's good to 0 celcius.

Cost, and that I do like to fiddle with MYOG, prompted my fleece bag project. The WM look like nice bags though.

Ticklebelly

[maxwellbest]

Yes that WM gear does look nice. Does Macpac do anything similar? Purely to take advantage of the Xmas sale...Or MD for that matter? (Must stop spending money on gear, must stop s.....)

[JohnM]

Macpac bags are nice, but I've never had anything like WM in the warmth for weight/compressibility to be honest. I haven't seen them all, but they're the best bags I've ever seen.

But the rrp of the Macpac bags is pretty high, so even at the sale price they're pretty close to WM.