Was planning on getting an Alpkit one but unable to find on there website!! Something down to -15 with a big hood. Budget around £130.
Obviously the above wants need to be taken into account!
Ta Richard
-15? Where are you going? Slept on glaciers in a -5 synthetic bag before.
Mountain Hardware Lamina 0 will take you to -18 ish and can be had for that sort of money, I've a Lamina 35 and it will cope with about 1 deg c, Lamina 20 will do you in the UK most of the year.
err does wind chill not come in to the equation most of my nights out are in the Lakes on a top somewhere! felt the cold last time I was out and it was +2 but windy as and woke up every 30 mins the bag was rated down to -5 and I slept with layers plus hat on!
Bivi bag/tarp to block the wind.
Was in a bivi and wind was to strong to erect a tarp(was behind a wall) and tarps are noisy. Planning on getting out this winter and sleeping in snow holes on the tops!
Lamina 0 should do the trick but you could opt for a warmer, lighter bag and a silk liner to give you a bit more flexibility.
silk liner sounds kinky!!!
Will check out the Lamina o
Try cotton and fleece liners as wall
silk liners are the business and what you need is a good air mattress under your bag because without one you are going to freeze your arse off in a snow hole.Have a look at the bearbones.co.uk site, there a wealth of bikepacking knowledge on there.
got an alpkit mat that I use inside my Bivi bag do I really need the faff of a liner!
I never wanted a liner, thought I would get tangled up in it, but it's fine. Silk doesn't add much in the way of warmth but it helps, plus it keeps your bag cleaner.
The bestest thing I ever got for winter bivvying was one of these:
Whitby Hand Warmer,
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It's like a hot water bottle but stays warm for about 6 hours. Clearly there is some kind of combustion going on so don't seal yourself inside your bivvy bag and expect to not get monoxide poisoning...
mmhhh better to play safe and use the warmers that you shake to get warm,one of those in your groin area will get blood to your toes warmed up pdq, another trick is to get some closed cell foam matting between your bivi bag and the cold ground, see bearbones site for more info, ps there is little or no faff with a silk liner
This year in -10 nights in Scotland, I found putting my foil emergency blanket on the floor of the tent and Prolite on top seemed to help.
I use a ME bag, but it only works when you use every baffle,cinch and drawstring .
Those air activated ones will add warmth but they don't add much. I've had half a dozen nights in my bag with the whitby warmer, on an inside pocket on a bitterly cold winter ride etc and no problems.
[url= http://thewirecutter.com/reviews/the-best-hand-warmer/ ]Good review here of the Zippo branded version[/url]