Words by Dom Haseldine
For a person that has laboured with a large synthetic sleeping bag for the last 5, years the Ascent 500 is an absolute treat!
So, first let’s cover the specs; the bag itself has a Pertex Microlight inner and outer with a filling of hydrophobically treated 650 fill-power duck down which is put into trapezoidal shaped baffles to help alleviate cold spots and increase thermal efficiency. It weighs just 1125g, comes with a cotton storage bag, a compression stuff sack and has a generous mummy shape. The comfort rating is 1C, the lower comfort limit is –4.5C and the extreme rating is a massive -22C.
Seizing the chance to review the Ascent 500, I swiftly planned a bivvy out in my back garden (Hay Bluff) at the end of November to allow the bag to flaunt its pros and cons. I checked the weather for Hay Bluff that evening, a cool 2 degrees with 50/50 chance of fog; a fair challenge for most down sleeping bags due to the wetter conditions. Although my synthetic bag has a comfort rating of -5C, it’s very large and took up most of a 50 litre rucksack; this is where the ascent 500 for me really showed its potential. It tucks neatly into the lower section of my rucksack in a dry bag with the compression stuff sack over the top, I wasn't going to take any chances. I ventured onto the Bluff, leaving the house at 6pm. It was dark by this point, the conditions were cold with a slight breeze but clear.
I had an enjoyable walk up to the Offas Dyke path, heading along the cats back towards Longtown to find a suitable space to bivvy down. Looking forward to jumping in the sleeping bag, it didn't take long to find a good spot which was suitably screened of from the wind. Swiftly laying out the bivvy bag, bed and sleeping bag, I packed my rucksack into a drybag before piling in for the night. Once in the bag, it didn't take long to appreciate the subtle differences between my two bags; the down gave an almost duvet feel with a noticeably warmer temperature. The two cinch cords at the top of the bag were also extremely beneficial, helping to trap the heat in and keep the cold out. The generous fit of the bag was a welcome change having tried several alpine bags which taper in and trap you like a straight jacket. The Ascent was exceptionally comfortable and completely in its element.
Apart from a lost or malicious horse stomping past very closely, I only woke up once in the early hours due to a moisture build up in my bivvy which had formed from the fog that had developed overnight and dripped on my face; met office strike again! The sleeping bag surprisingly managed to put up a very commendable fight against this! The outer of the sleeping bag had patches of beading water with a few sections beginning to soak through slightly. This was most likely down to the ridges in the bed I was sleeping on collecting water and my weight pushing the bag into them. After re-packing the rucksack and having a quick bite to eat in the morning, I set off on my return journey.
Shortly after returning home, I got the bag out and laid it on the table, giving it a quick wipe where necessary. Very little moisture had absorbed past the face fabric and the down had hardly clumped at all, which was unexpected due to all the moisture in the air which had formed on the inside of my bivvy. If the bag had not had hydrophobically treated down I may have been a little more cautious, however, the aim of these reviews is to push the Ascent past its comfort zone!
Overall the sleeping bag handled very well around its comfort limit with very little cause for concern, giving me a very comfortable nights sleep and coping well with the adverse weather conditions. Although the bag would be perfect for drier conditions given the nature of down, the Ascent handled its first damp outing without any issues. The large amount of space in the bag is a very welcome change from narrower, less comfortable bags and the cinch cords make it easy to warm yourself up after a cold slog up the Black Mountains.