Yeah, I know the Wiggy's bags can be vacuum packed but I haven't done it. But I have left them stuffed tightly rolled in stuff sacks for long periods of time without loss of loft. Disclaimer: I'm not affiliated with Wiggy's but I do have five of their bags!

An outward bound school I worked at had probably a thousand sleeping bags, mostly slumberjack and including a few hundred Wiggy's. They were all 20 degree synthetics. There seemed to be no difference in loft or warmth between brands and after several months of use they all were colder by a noticeable amount. In the CA Sierra Nevada, summer temps were sometimes down to freezing and the more used bags were not warm enough. Even sleeping in long underwear and fleece, the students with the older bags were cold.

I'd say store then in loose cotton bags - a big pillow case is good. and not in the basement or attic either.

When that happens you just throw the bag in the washing machine. That brings the loft back.

Believe me, these were well washed bags. Synthetic fill just wears out quickly.

I'm not buying it. My oldest one is over 10 years old and hasn't lost a bit of loft. Send it back then- two months or twenty years old Wiggy's will replace or repair it.

I don't know what they did with them. I didn't see them buy more in later years. They bought more of the slumberjack/kelty type bags.

Chaosmagnet,

Your Military bag is probably a Wiggy's. The tags should say if they are still in place. They are the prime and original manufacturer of the set you bought. The older style (which I think is what you have) are often available surplus or from former GI's for really good prices. Wash it as shown on the Wiggy's site, stuff it up, and be ready for serious cold. Not the lightest or most compact, but a serious cold weather bag at a super price. Just right for your need. I have and will trusted them for a while as my survival sleep system (in the car, in the airplane, in the canoe, sometimes even backpacking).

I agree, some of my worst nights were stuck in a snowbank type nights (usually on the plains of Wyoming or Montana, the wind gets nasty sometimes).

Respectfully,

Jerry

Consider the impact of a few consecutive weeks using your bags in the outdoors. I've been out 17 days and my sub 1 kg bag weighed more than 4 lbs. Body condensation. It has a cumulative effect on loft and sleeping temperature. You can sorta feel it later on a trip but generally after a couple weeks you're such a bad ass hiker it doesn't bother you so much.

I noticed my 11 year old sleeping bag which has been stored compressed the first 2-3 years, has lost considerable more of it's insulation than my 19 year old sleeping bag which has been stored loosely all it's life...