[Closed] Lightweight synthetic sleeping bags

Look at the Mountain Hardware Lamina range and choose according to your warmth requirements? That Marmot looks excellent at that warmth:weight ratio though.

That Marmot one looks good, but how realistic is the comfort rating? The specifications page on that website actually has a comfort rating of 0.5deg. C with a 'lower' comfort rating of -5 deg. C.
I would probably be assuming the comfort rating is actually 0.5, rather than -5. Although that would presumably still be fine for spring to autumn.

Personally I would find that bag a bit small at the foot end, which is probably part of the reason it has such a low weight although if you don't think that would be an issue for you then it looks like a good option.

I have a Lamina Spark (I think) from a couple of years ago, sadly not really been able to test it due to general life nonsense, but it looks and feels lovely! 🙄

All I would say is watch out for stated weights, the stated weight for the Lamina Spark was at least 15% out (from memory something like 900g vs. 750g stated). It's still light but it was annoying as I might have discounted other bags because they were 'heavier' but in reality they might not have been. Could have saved a bit of money or got something warmer etc.

I use an OMM one, it's very light, but if it's chilly then it's a "sleep in your clothes and hat" job. Which is fine by me anyway if bike packing as otherwise it seems like you're just carrying extra weight.

same as honeybadgerx, I'd be thinking in terms of Sleeping bag + tomorrows clean dry baselyers + camp duvet jacket (something like a Rab Microlight or equiv synthetic), things you'd be taking anyway. So the Marmot will prob be fine but also with the usual other caveats of it depends on how warm you sleep, what sort of camp mat you use, whether you have a hearty meal or not, how dry you've got yourself from the days exercise, under what forecast/conditions you're going to bail out etc etc

I like the look of the omm bags, don't mind sleeping in a jacket (puffer)...but if the puffers is wet and dirty...and there's no point carrying extra sleeping clothes as I might as well have a bulkier bag

Also have a lightweight OMM one but it doesn't even have a temperature or comfort rating. From experience though it's fine down to 12 degrees C, is ok down to about 5 C with clothes on and in a bivvy or tent. Not really made for comfort more for racing.

My Rab one is more substantial but also about 1300g.

Is there such thing as a 3 season bag that is sub 1kg, pack size about 300 X 150 and less than £200?

Is there such thing as a 3 season bag that is sub 1kg, pack size about 300 X 150 and less than £200?

It depends how you define three-season, but possibly an Apkit Pipeddream 400:

https://alpkit.com/products/pipedream-400

The problem with lightweight down sleeping bags is that both high fill power down and ultra-lightweight fabrics are expensive. On the other hand, down lasts for ages if looked after, so you can always reframe the initial outlay on a maore expensice, top notch bag as a long=term investment.

Pipedream 400 here, bought it as a lighter bag for using on a 5 day Cairngorms walk. It came last april, I was keen to try it out - first weekend that I could, I went for a wee quick summit camp on Craiglee (Galloway hills) and it turned out to be the coldest April night in many a long year, -8 locally.

I was fine, never felt cold at all apart form my big nose sticking out, but this would also have been down to having a good insulated mat too (Exped Synmat 7).

Are there synthetics now that compete with down on weight and pack size? If in a tent, I use a down bag with a silk liner, with a drybag (or even double bagged) instead of the stuff sack. The silk liner adds warmth and means sleeping in previously worn clothes doesn't get the bag dirty (clean clothes are not feasible on week long kayak trips).

Are there synthetics now that compete with down on weight and pack size?

Not until Patagonia starts using the stuff in its top-end synthetic jackets in sleeping bags I think. They would presumably be stupid expensive - like the jackets - but potentially work really well. I wonder if there are constraints on the way its used that make it problematic for bags. Or maybe they figure that a synthetic bag costing as much as a top-notch down one has a very limited market.