Topic

Extreme cold synthetic bags


Forum Posting

A Membership is required to post in the forums. Login or become a member to post in the member forums!

Home Forums Gear Forums Gear (General) Extreme cold synthetic bags

  • This topic is empty.
Viewing 2 posts - 1 through 2 (of 2 total)
  • Author
    Posts
  • #1282871
    Andy F
    Spectator

    @andyf

    Locale: Midwest/Midatlantic

    Anyone using an extreme cold (-20F to -40F/C) synthetic bag? I'm interested in hearing your experience with:

    1. loft reduction over time
    2. Pack volume: what's your pack size/volume, and how much does the bag use up (photos helpful here)
    3. comfort and warmth
    4. include specific model and insulation type if possible

    Why I'm asking about this:
    I have a 0F 600 fill power down bag (Marmot Never Summer 3 lbs, 15 oz) which I'm considering extending down to -30F with a vapor barrier and 30F outer bag (Montbell #3 down stretch, 21 oz). This combination would weigh 5 lbs, 4 oz, which appears to be only 9 oz less than a -40F Primaloft bag) A quick test of this in the backyard reveals that it's probably possible with little loft compression, but getting the outer bag zipped up while inside is challenging at 26F. I'm not sure that I'd want to try it while dressed in only a base layer at -26F!

    #1810633
    Fog Mountain
    Member

    @fogmountain

    I have a North Face Igloo HV (long), which is (gasp) 17 or 18 years old now. It's insulated with Polarguard HV, and rated to –25°F. Its rating is pretty accurate—when it was nearly new, I slept comfortably in it at –28°F, inside a double-wall tent and a bivy bag. I believe it had about 12 inches of total loft when new, and it's down to 10 inches now. I believe most of the loss of loft occurred in the first few years.

    It weighs 6 lbs, 2 oz. It stuffs (with some difficulty) into a 13" x 24" stuffbag. That's about 3200 cubic inches, or 52 liters. I never had an internal frame pack big enough to carry it internally along with winter clothes. I used to carry it strapped to an external frame pack. I've since switched to down.

    I'd be very suspicious that a Primaloft bag weighing less than 6 pounds would actually be comfortable at -40°F.

Viewing 2 posts - 1 through 2 (of 2 total)
  • You must be logged in to reply to this topic.
Forum Posting

A Membership is required to post in the forums. Login or become a member to post in the member forums!

Get the Newsletter

Get our free Handbook and Receive our weekly newsletter to see what's new at Backpacking Light!

Gear Research & Discovery Tools


Loading...