Down filled or hollow fibre

[R3XXY]

Hi all, does anyone have direct experience of a down filled sleeping bag ?
I'm in the market for one of those arctic military bags that everyone likes so much, but I don't know whether to get the down filled one or the synthetic filled one.
I have a feather duvet at home which I love and was outrageously warm when it was new, but it has lost it's loft a little bit over the years, also I've heard that the down filled military bags are MUCH older than the synthetic ones.
Any advice would be greatfully received, thanks in advance.

 

[Shewie]

I think the older army bags are feather and down so not strictly a pure down bag as we know today. I used to own a couple and they were great but they are heavy and don't pack down too well. I've no military insight and I was just using them for casual camping, but I get the impression they were built to last and so weight wasn't really a concern.
Arguments for down and synthetic have gone on for eons, modern down bags can compress down ridiculously small compared to a sythetic bag of the same temp rating. Sythetics have been regarded better for damper climates but now modern down bags have better protective outer shells and it takes a pretty dumb camper to get one so wet to be unuseable.
A well looked after down bag should see you right for many years, picking up a used ex army issue bag is always going to be a gamble especially if ordering online without seeing it first.

What sort of temperatures are you looking to camp at ?

What's your budget ? There's some great bags out there for a good price, Alpkit are worth a look if you're buying new.

Hoipefully you'll get some first hand squaddie info soon though.

 

[rik_uk3]

Synthetic army arctic bags are bulky but will handle ANY temperature the UK will offer.

 

[RobertRogers]

If you think your bag has the chance of getting damp or wet, then synthetic may be the best choice.

Down is useless when wet and is difficult to dry in the field.

Synthetics are heavier and bulkier but retain more insulating value if damp and are easier to dry out.

 

[Adrian]

Depends. I've used down bags a lot, and there is no synthetic filling that I've come across over the years that compares for weight and pack size. A -30 down bag will be lighter and pack quite a lot smaller than a -30 synthetic. Down is also more comfortable in temps higher than rated - so where the synth bag above gets sweaty in a warmer temp, the down is much more comfortable.

Down, however, loses all insulation when wet - and is a right sod to dry out, so use of a bivvy bag or other vapour-permeable cover is essential if there is a risk of dampness - condensation in a tent/snowhole, or damp/rain under a tarp. There are bags that are made with a waterproof, vapour permeable outer shell - Tundra bags are supposed to be excellent, but any such bags are pricy.

Synths are cheaper, and for the same temp rating are heavier and bulkier - can be quite a lot heavier and bulkier! They are generally a bit more robust, and not as vulnerable to losing insulation when damp - remember though that ANY bag - regardless of filling, will lose insulative effect when wet, and so should be protected if there is a risk!

I currently have Nanok bags - the 0 and -25, and they are excellent, but they are heavy. I used the Nanok in Norway, and good as it was, if I get to go back and skitour again, I am very tempted to spend the money on a proofed down bag - purely because of the weight/bulk issue. A good night's sleep really is priceless!

Actually, the best synth filling I've found was in a Rohan bodywarmer - stuff called Primaloft. It's the closest I've found to down performance, but I've never seen it used in sleeping bags by anyone!

Remember as well, that ANY bag - regardless of filling, will lose loft and therefore insulative effect with time, and this is accelerated if it is stored incorrectly.

 

[R3XXY]

Thanks for all thw feedback guys, I think I'll be going for a down filled bag.
I have a bombproof bivi bag so dampness isn't a problem.

 

[andythecelt]

I have both the Military arctic synthetic number and the older arctic down bag. It's not a fair comaprison really because the synthetic one was brand new when I got it and the down jobbie was an old thing picked up for a song at a car boot sale. I've used both but only the synthetic one in real cold. I must say it's fantastic and I've always been toasty in it but it's bulky as hell. I use a full sized bergan and the bag half fills it. The main reason I'm dubious about the down bag is its age. It's had a few repairs and moults feathers so I'd rather not chance getting cold at night by talking it out in winter. It was no doubt a cracking bag when new though so I'd love one in mint condition. I suppose the bottom line is when it's cold I always take the synthetic bag and bivvy as a cover. I can be guaranteed a good kip that way no matter what the weather does. Last time I was out my tarp developed a leak (it had been hammering it down all night). With the bivvy over the bag I just thought "Bugger, need to fix that sometime", rolled over and went back to sleep.

 

[wentworth]

If you can afford it, go for a down bag with a fill power of at least 800fp. You won't believe the difference.

 

[R3XXY]

what does fp stand for ? I secured a deal for a down filled military arctic bag today, he assured me it was in good condition, said it was an 8-9 out of 10.
I was half considering a Snugpak softie 15 but they look quite cramped and I'd rather swap my softie 5 than spend more cash.

 

[wentworth]

fp is fillpower. 800fp if i recall correctly means that 1oz of down will loft up to fill 800 cubic inches of space. The lower the fill power, the less space 1oz will loft up to fill.

Generally military bags are a down feather mix.

 

[Mike_B]

A (good) down bag will last a very much longer time than a synthetic one - my RAB bag is over 20 years old and still perfect. One of the advantages of buying a down bag is that it can be "topped up" with extra down if necessary.

Mike

 

[R3XXY]

I'm going to get hold of one of each, try them out to see which one I like best then move the other one on. Or maybe I'll just keep them both
Both of the people I'm swapping with seem very happy with how their's performed and have assured me that they're in excellent condition.
i'll keep you posted. Quite interesting to see all the different experiences, pros and cons and points of view.

 

[Noddy]

...............

 

[wentworth]

Yeah, for the weight of a synthetic bag, I could carry a down bag and another down bag as a backup!

 

[strideredc]

Synthetic army arctic bags are bulky but will handle ANY temperature the UK will offer.

hammock camping with my 88pat? synthetic and my wifes 58pat? feather bag we woke up freezing in the end of august!!!

that was bag directly on the hammock, but it wasnt the back that was cold it was the top part that wasnt compressed

i think i will get an alpkit down one soon, is it a good idea to get a roll mat under the bag?

 

[rik_uk3]

hammock camping with my 88pat? synthetic and my wifes 58pat? feather bag we woke up freezing in the end of august!!!

that was bag directly on the hammock, but it wasnt the back that was cold it was the top part that wasnt compressed

i think i will get an alpkit down one soon, is it a good idea to get a roll mat under the bag?

This is what I have
http://www.semma4.co.uk/shop/product_info.php?products_id=119

 

[R3XXY]

I have one of those arriving very soon rik_uk3, from a swap with another BCUK member . Perfect weather to try it out, how do you like your's ?
You ever used it in sub zero temps ?