Fathom EV 300 Sleeping Bag

I've only ever owned 3 sleeping bags, an oex fathom 300, a rab neutrino 200 and a decathlon mt900 0 degree The fathom was synthetic and just over 1kg, I have to say I was very impressed with it and used it down to 0 no problem (I sleep warm tbf) it's only negative was it's pack size. The decathlon was very impressive packed up small and was around 900 grams and £170. Sadly I was too tall for it so was passed on to my partner who was still using a fathom. The Rab neutrino was a huge let down and Rab must have been high when doing the temp rating for it, the cut of it was also very restrictive it quickly got sold and that led me to quilts. For your needs the decathlon would probably be ideal. My main suggestion would be avoid low fill power down, I personally aim for 800+, 700 at a push. And be wary of companies temp ratings (looking at you Rab and thermarest)

The Rab cost 250 and is marketed and being useable down to -1, simply not true with 200 grams of 800 fill down. also looking at the Rab website it appears I'm not the only unimpressed with it. The oex like you say is a cheap bag and is great value for money so of course I'd be more happy with a bag that cost 45 quid and exceeded expectations than one that was 250 and completely underwhelmed me. Then there is the shape the Rab is ridiculously tight! To the point it made me move away for sleeping bags. Both bags used around 0 on the same mat and I found the oex warmer. I had a thermarest corus that like you say "lofted up 3 times thicker" however that's another product that wasn't fit for purpose. Huge horizontal baffles with 650fp down, only ends one way lol.

I've not owned the Neutrino 200 but I've owned numerous Rab sleeping bags and have always found their temp ratings somewhat reliable. My current winter bag is the Neutrino 700. I also own the Ev300 and think it is a good value for money bag and I have used it a heck of a lot and it's proved to be very durable, but I think their temp ratings are absolutely absurd. If temperatures are forecast to go below about 8C I take a different bag. Regarding the Thermarest quilt, I agree with you, the down migrates a lot, but if I give the quilt a gentle shake along it's width and along it's length and give the quilt a good amount of time to loft, I find there's not too many empty areas. I certainly find the Corus 32 warmer than my Ev300.

The Rab figure is limit, not comfort. I agree with you there, lab tests are flawed and inconsistent and should be taken with a pinch of salt. I actually spoke with Rab about tests and they told me that you can get different results on the same bag at the same facility! Alpkit actually test their sleeping bags using the Leeds Comfort Model and then interpolate the results to get an equivalent EN rating. How they do this I have no idea, I've found no table or calculation that converst standards. This surely has the potential to introduce further inconsistencies. PHD don't even test their sleeping bags in a lab because they think it's pointless. When I'm looking at down bags or quilts, I always calculate the cubic inches using the fill weight and fill power to give me an idea of what sort of temperature it might be suitable for. Oex are the worst I've seen for making wild temperature claims. For instance, on the Go Outdoors website, they state that the Ev300 will keep you comfortable down to -5 which is absurd, unethical, and potentially dangerous.

Yes, good article. I have quite a few sleeping bags and quilts and there's a vast difference between the thickness of the Ev300 and others with similar temperature claims. I did actually take a set of photos of each bag showing the different thicknesses. For instance, I have a Thermarest Corus 32 which, if I remember correctly, actually as higher temp ratings than the Ev300 but is about twice as thick. I'm a warm person, I cold shower year round, wild swim etc. but would never take my Ev300 camping in temperatures below about 5C.

No. The Fathom Ev300 is a 2-season sleeping bag (regardless of what Oex claim). Ditch the foil mat too, they're pointless. You really need to invest in a good, 4-season sleeping bag. Mountain rescue teams in South Wales have already attended callouts with hypothermia this winter, and up until this week it's been relatively mild!

The Go Outdoors website state, about the Fathom Ev300, 'will keep you comfy down to -5°C'. It's absolutely absurd. This bag won't keep you comfortably warm at +5, never mind -5.

I have an Oex Fathom Ev300 and to give an idea of what this bag is like, I also have a Thermarest Corus 32 which has a comfort rating of +5, and which lofts to about roughly 1.5-2x the thickness of the Ev300. Where Oex get their temperature ratings from I don't know.

Please take what random people on social media say with a big pinch of salt. You can never be certain they are being truthful, and neither do you know the full details, for instance, was that ambient temperature or wind chill? Was that forecast temperature or actual measured temperature? Was that internal or external temperature? I took some photos of various sleeping bags and quilts that I own showing the different amounts of loft each has. Here is a Thermarest Corus 32 which has comfort and limit ratings of 5c and 0c, respectively. https://preview.redd.it/73hr0r8i9seg1.jpeg?width=4276&format=pjpg&auto=webp&s=811921f9a8c01d963602c74f137802319fc89274

And here is the Oex Fathom Ev300, which is thinner than the Thermarest yet is supposed to have comfort and limit ratings of 1c and -5c, respectively. These temperature ratings are an absolute joke and borderline dangerous. https://preview.redd.it/euwnfe9k9seg1.jpeg?width=3838&format=pjpg&auto=webp&s=1496752b243b205da375b0337d9372fe4be2d284

I find -1 in the Oex Fathom Ev300 very hard to believe, and that's putting it politely.

I have used mine in single digit temperatures. iirc I've been out in around 6c and felt cold hence why once we start getting into single digit temperatures I just swap to a warmer bag or quilt.

The Ev300 is a 2-season sleeping bag, the Ev400 a 3-season sleeping bag, imo.

Oex's temperature ratings are seemingly plucked out of thin air. The Fathom Ev300 is a 2-season summer sleeping bag regardless of what Oex or Go Outdoors claim it to be. I wouldn't take mine out in single digit temperatures never mind below freezing.

Looking at the sleeping bag you have linked, it seems like the -11 rating is the extreme temperature rating (meaning it will keep you alive at that temperature, but you risk frostbite & absolutely won’t be able to sleep) If you are able to stretch an extra fiver the[OEX fathom EV 300](https://www.ultimateoutdoors.com/16560003/oex-fathom-ev-300-sleeping-bag-16560003) will be much warmer and as a bonus, is lighter and smaller to pack. If £50 is the absolute limit, you could look at the [Berghaus transition 300](https://www.ultimateoutdoors.com/16559968/berghaus-transition-300-sleeping-bag-16559968), similar levels of warmth, just twice the weight and a larger pack size Both of these sleeping bags should cover you from mid-spring to mid-autumn in terms of temperature range.

Ive got the Fathom! Ive used it in spring/summer/ early autumn and it was fine. Great even considering the price and the size. Wouldn't use it in freezing temperatures though, I have another bag for that