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Spence
12-11-2004, 07:37 PM
Although I'm a warm sleeper, I had to tempt fate this year and push my 40 degree bag beyond it's limits, and ended up cold at night around 32 deg. I solved that with the use of my emergency space blanket that made a world of difference. I really love packing only 20 ounces of sleeping bag, and want to keep from taking my winter bag if possible. What experience have folks had with lightweight, reuseable bag liners that would bridge this gap? At the time, I was dressed in dry undergarments, fleece pullover, socks and fleece hat. I think a liner would be more useful than 5+lbs of extra clothing.

Dale Lindsley
12-11-2004, 09:07 PM
For 20 oz. you could carry another sleeping bag. Then just put one inside the other. Another possible angle: make sure you've got real good insulation below. If you're using a Thermarest, you might put a "blue foam" pad under it. Being a geezer, I would rather carry a 6 pound sleeping bag than sleep cold, more power to you.

Ralph
12-11-2004, 09:11 PM
Dales suggestions are good. An inner sleeping bag can be very light and should have an untreated/uncoated exterior. Check the inside masurement of your sleeping bag and try to get one a bit smaller (squishing the insulation is ineffective). Campmor, EMS and REI all carry various makes of microfleece liners that are pretty good. Thermolite has one for about $70 (EMS) that is guaranteed to add 15 degrees to the bag, but I can't vouch for it. Their other products are good, so I have no reason to think this wouldn't be. It's also compact, as I recall it's about 4" dia x 6" or so in its own stuff sack. Probably could be left in your bag and stuffed into the same stuff sack.

I've seen liners in cotton and silk as well as nonwoven nylon but I'd stick with the microfleece.

The fleece bags will surely increase the range, and are light but a bit bulky, 2-3 times the size of the microfleece. If you have room in the pack they are worth a look.

You might also consider a light overbag/bivy sack.

I'm in the Adirondacks and early season can vary a bit in temperature (to say the least). I have taken to carrying the Thermolite emergency sleeping bag as an overbag. This is an aluminized fabric bag with foot ventilation - not as stiff as the space blanket nor as fragile as the rescue blanket. I used it once last year and it did seem to add warmth in my unscientific judgement. Thermolite also makes a blanket style. both are around $20-25.

Spence
12-11-2004, 10:05 PM
Thanks for the input. I looked at that Thermolite in EMS, 15 degrees extra at only 9 ounces?? Hmmm.. sounds a bit optimistic. Worth a look, I guess. Looks like REI has some similar models that I'll have to check out.

Ralph
12-12-2004, 05:47 PM
I think it may be optimistic, too. It is also about $60 as I recall, so I don't have one. - yet.

Liners can be surprising, though. The space between the liner and the inside of the bag can be insulative, too, this may have something to do with it. It is also a lot easier to wash a liner than a whole sleeping bag.

RD
12-12-2004, 07:08 PM
Spence,

What you experienced with your space blanket was one of the unique albiet fickle aspects of a vapor barrier liner. Your space blanket helped keep the moist air around your body and the shiny surface reflected the infrared heat back as well. Warm air holds more moisture than cold air and moist air holds more heat. Western Mountaineering makes a vbl liner bag with the same characteristics as your space blanket, weighs about four ounces, lasts much longer, and costs about 18 times as much.

If you would like a good discussion on vapor barrier go to http://www.warmlite.com. A person can save a lot of weight by their use and gain up to ten more degrees F in sleeping bag range.
Have fun, RD

Spence
12-12-2004, 10:02 PM
RD,
Thanks for the link, very interesting reading. My next step was to experiment with a trash bag as a VB for kicks.

rambler_wannabe
12-14-2004, 09:29 AM
I can vouch for the thermolite--it looks like nothing more than T-shirt material but put it inside a shell and it is incredible. I think it is about twice as effective as the silk liner I was using before and a lot more durable.

My only complaint the size--it is too short for me so I usually just cinch it below my armpits and go with it.

rambler_wannabe
12-14-2004, 09:55 AM
Be careful w/ VBL's, they work very differently above 30F than they do below, I wouldn't mess with one until below 0F.

You may not be able to get a second bag for 20 oz (since it needs to be big enough to layer with the one you have). I am a firm believer in the overbag concept when done right--it can add so much flexibility for very little weight gain. I have a 35F bag, the thermolite liner (8 oz w/o stuff sack) and will build/buy something like a Big Agnes Cross Mountain or Yampa. My total weight for the winter kit may be about a pound heavier than one bag for the same max rating but I will be COMFORTABLE anywhere from -10 to 70 which is a nice feature when a trip includes several thousand feet of elevation change between camps and shoulder season for weather.

Ralph
12-15-2004, 06:32 AM
I am going to look very seriously at that Thermolite liner. Even in midsummer around here the nights can get downright chilly, Having a compact way of adding 15 degrees is very attractive.

As a boy, before I got a sleeping bag (pads weren't invented yet) I used blankets. One folded in quarters beneath me as a pad and one or two wrapped around and quickly found that 2-3 lb blankets were warmer than 1-6lb blanket because of the extra trapped air between them.

Spence
12-15-2004, 10:50 AM
I agree, they look good. I see that Campmor sells them for $20. Where abouts in NY are you at Ralph? I spent 3.5 years rambling through the Adirondacks while stationed at Ft Drum, loved every minute.
Spence

Ralph
12-15-2004, 05:47 PM
I'll have to check Campmor.

I live in the Mohawk Valley (just down the road from some Mohawks). I spent a bit of time at Drum, myself, 3/42 Arty. As far as I know, Drum has the only artillery range east of the Mississippi that can take heavy artillery.

Spence
12-15-2004, 06:33 PM
I'm not an artillery expert, but they do have a nice range complex. What I do know is that the Mohawk River is a great spot for late season ducks and geese. I hope to get back there sometime in my career.

Ralph
12-16-2004, 01:44 PM
Several flocks of geese flew over my home today. The ducks are there, too, but they are not as talkative as the geese. The area I live in is right on one of the spur flyways.

Patrick
12-16-2004, 02:09 PM
I just read Gen. Frank's biography. He was an artilleryman too. I learned respect for the art from reading the man.

Ralph
12-16-2004, 06:00 PM
Artillery is the most technical of the combat arms. Most of my service was with 8" howitzers. You want MOA shooting? Try throwing a 296 lb. projectile in excess of 20 miles and reliably hitting a target the size of a car body. Routine for the 8", the most accurate artillery ever made. Trouble is it's big and heavy (the towed version is 26,000 lbs, self-propelled adds about 20 tons for the track body. Hence, no longer in the inventory of a light, mobile army. I, and many other heavy artillerymen think this is a mistake. Park a battery of 4 of these in the middle of things and you cover a 40+ mile circle, able to deliver a half-ton of iron on target within a couple of minutes.

I'll look up that biography, sounds interesting.

Dick Blust has a post in the Hunting section about possible shutdown of GPS. This could pose a problem since GPS is the lifeblood of modern artillery and I'm unsure about the manual skills being trained today. To be accurate the guns have to be precisely located. I was the recon and survey officer of the battalion, and my crew would survey the gun positions. Nowadays they use a GPS.

GPS is also used to navigate in areas without a lot of landmarks (like the desert). Without it you have to use dead reckoning. This works, but is much slower and prone to error. All things considered, shutting down GPS would be a desperate act causing many more problems than it solves.

shu
12-17-2004, 08:52 AM
Ralph-

I am also curious about the manual skills being trained in today's military. Even 15 years ago, we spent a lot of time using map & compass where it seems now everything is done with GPS. I can only assume that, since we always trained as though most other contingencies had failed, they continue to do so today. From all indications, the men and women in today's armed forces are just as capable as we were.

Ralph
12-17-2004, 06:47 PM
Yes, and we were as capable as the guys who fought WWII. I do know the field artillery is not spending as much time training manual fire direction as they did, from what some of my old red-leg buddies have told me.

The computer has changed things a lot, but I shudder to think what might happen if someone manages to generate selective EMP that can fry unpotected computer systems (including the ones that make most vehicles work today).

All of the newer weapons systems I have seen have manual backups. You sacrifice speed having to load a howitzer by hand, but at least you can still shoot. The modern tanks can fire accurately while moving only because of the automated systems aboard, but the old stop & shoot will still work, though not as desirable.

As an FO, I could, in dire need, fill in for an FDC, though I wasn't nearly as fast or as accurate, not being set up for that, but I could bring fire on target. I certainly hope we haven't sacrificed that capability.

I was the training officer for the specialist battalion at the artillery training center at Sill (FDC, surveying, flash & sound ranging). I'm familiar with the problems of trying to get maximum training within the limited time available. It is not an easy task, but you have to understand the why as well as the how.

imported_kutenay
12-19-2004, 06:17 PM
I don't know anything about artillery, unless my .45-70 Bear loads qualify, but, I do know a bit about sleeping bags. Where I live, a good sleeping bag is not a luxury, it is a necessity as people die from exposure, every year within sight of the lights of Vancouver; the interior has much harsher conditions.

I hate sleeping bag liners and never use them, although I have done so, extensively, in the past. I find that a bag liner plus bag is heavier and less compressible than a good bag, this is relative to temperature suitability, of course and, the supposed advantages are mostly imaginary.

There are, IMO, THREE really crucial pieces of gear for serious wilderness rambling, one is your sleeping bag. I don't know how many young people I have had come into the large equipment store where I worked before I retired, wearing $600-700.00 Gore-Tex parks suitable for an Everest climb and then try to skimp on a sleeping bag purchase....way bad, foolish and just wrong!

Right now, I have four bags, but, could get by with two or three for EVERYTHING in western Canada. I want a -30 to-40 Endurance and down bag, this is the expensive one and the foundation of serious winter camping, I use mine in the spring and fall as well. This is where you spend the bucks and, if looked after, this bag will last a lifetime. Western Mountaineering, Feathered Friends, Integral Designs in North America, nobody else really compares, IMHO.

I also need a very light summer bag for backpack flyfishing trips during high summer, July and August. The previous makers have a number of models available, Western has a specific line that is just fabulous.

I also like to have a synthetic "beater' bag for carrying on my packboard while hunting, in my vehicle for emergencies while traveling and using when day hiking with an ancient "Early Winters" G-T bivy from the '70s. This will keep me alive if I go down with an injury, yet, it is cheap to replace if damaged by rough use.

I realize that many people need to be careful about gear expenditures, due to family responsibilities, educational goals and the concomitant cost or are just too frugal and wise to spend a lot on gear, especially if they live in more temperate climates than I do. I see a place for liners, under these conditions, but, for serious use in wilderness conditions, I recommend getting one top quality bag, a bit warmer than you think you might need and using it, for everything. It worked for me, for many years.

shu
12-20-2004, 06:49 AM
Its a lot easier to show off that GTX parka around town--you ever tried wearing a down bag at an apre-ski swar-eh?

Jon
12-21-2004, 10:15 AM
Just wanted to say that Military surplus Goretex Bivy sacks are affordable on ebay. I just got one a few days ago, with the black (medium-weight?) sleeping bag from the current-issue modular sleep system. Haven't tried it out yet, but it looks good. I've seen just the G-T sleeping bag covers go from $40-$100, and the Canadian/British bivies seem to go for a bit less (I assume because they aren't as "cool" as the U.S. camoflauge bivies).