Tuesday, 19 May 2009

New gear Reviewed, PHD Minim 500

Sleeping Bag - PHD Minim 500

Initial Impressions

I’d ordered the PHD Minim on the last day of the sale prior to setting off on the last trip. The amount of loft was amazing and even with a Half Zip and stuffed into a Sea to Summit Ultra-Sil roll top the weight was only around 900g. There seemed to be plenty of insulation and the hood looked good so I had high hopes for it, intending to use it as a winter bag and only taking it this time as it was the lightest bag I had even though I expected to be too warm in it. I opted for the Drishell outer and the bag looked the business, it came with a storage stuff sack and a normal stuff sack.

In the Field

I spent both nights in the bothy and I didn’t feel particularily warm. The 1st night I changed into my spare base layer and socks but felt a bit cold around my lower back. This may have been due to the lack of shoulder baffle but as I tend to wrap the bag around my shoulders with the hood up it’s more likely, given that I’m pretty skinny, on the amount of space in the bag as it isn’t particularily close fitting for me. The 2nd night I only changed into my spare socks but ended up sleeping with base layer, trousers, fleece, wind shirt and a Montane Flux and it still took a hot cuppa soup before I could get over to sleep. I’ll assume that my (quite possibly) slightly damp base layer was to blame this time as my feet were toasty in dry socks. Both nights I used a Pacific Outdoors Ether Thermo 6 mat, the 1st night on the wooden bench, the 2nd on the wooden floor.


I‘m slightly disappointed as I expected the bag to over perform given the time of year, I know that I need about 5 deg more than the rating for a Snugpak bag but didn’t expect to need it on the PHD, clearly I sleep very cold. I’ll certainly be careful to check the dimensions of the next bag I buy, particularily the width as I feel that too much extra space is part of the problem. The Mountain Equipment bags with the elasticated mid section might be worth considering but I’d be reluctant to buy another bag without a shoulder baffle in any case.


  1. Bags are hard to get right aren't they. Seems like you do sleep cold but it's an important lesson to learn. Ratings can be extremely missleading. On the Ajunkilak web pages there used to be a link to a report on bag ratings that was put together around the time the new Euronorm was layed down. It's the most comprehensive comparison of bag ratings I've seen. I remember there being about 15 degrees between the most optimistic and the most pessimistic ratings! The Leeds rating used by Cumulus (and PhD?) was amongst the more optimistic if I remember correctly. The ratings are of course based on performance as new. I wonder how quickly top end 800-900 fill down deteriorates? In any case pperformance is only going to get worse with age.

    Chris Townsends trick of ignoring the ratings and measuring the loft is the best I think. Measure the loft on your minim and aim for something higher next time.

    I don't sleep so cold as you I don't think. I now use a Cumulus quantum 200, rated to 0 degrees, but which gets me down to about 2-4degrees depending on my mat and if I wear extra clothing. Thats the deal I make. I carry long johns and down jacket in any case so I consider them as part of my sleeping system. It's not for everyone but I figue I get a more flexible system with the minimum weight penalty.

  2. I think that page you mention is still on the Mammut site, must take a look.

    To be honest I seem to have more sucess with synthetic bags, I wonder if there's more to sleeping bag insulation than just the amount of air trapped. Do some synthetic fills actually absorb/retain heat in a way that down doesn't, some synthetic materials actually seem to heat up/relfect heat back when you put your hand on them.

  3. Regarding synthetic fill I meant to add thaT I have a Montane Flux which is unbeleivably warm considering how thin it is, you almost get the impression the jacket id heating up. bizarre!!