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The lightweight version of the iconic Gamma range is a truly versatile soft-shell jacket suitable for all fast paced mountain adventures.
PROS
- Lightweight
- Excellent chest pockets
- Fully meshed front panels offer wicking and warmth
CONS
- Sleeve cuffs not adjustable (for closure)
- Generous in size
In my younger days (which was some time ago now) and soft shells had just developed from shelled fleece to a laminated or woven design there were two main contenders for top dog winter climbing soft shells. The Patagonia Mixmaster and the Arc’teryx Gamma MX, I owned both and they were awesome jackets – the Gamma MX just won out as the hood was better (this is vital for Scottish winter climbing as the spindrift can be so powerful that it can quickly fill a hood and force it off). The MX is still in the range so that’s a testement to how awesome that jacket is (it has had some modifications since then).
Since then the Gamma range has developed and become more versatile and suited to variety of general mountain activities. This makes sense as having one do-it-all style jacket means you buy less and use more. One new development is the Gamma Lightweight Jacket, a summer weight outer layer that is perfectly suited to hiking and trekking in warmer conditions. It’s the lightest weight jacket in the Gamma range – the CGR scales weighed in a size M at 322g and the stated weight is 320g so pretty much spot on. There is a hoody version which adds an extra 6g and a decent looking hood. Do keep an eye out for our review of the iconic Gamma Hoody later in the autumn.
Lightweight and comfortable, it worked great for sport climbing. You can see how the chest pockets are well placed for climbing harnesses.
The Arc’teryx Gamma Lightweight Jacket is stuffed full of quality features and premium fabrics, as you would expect from Arc’teryx. What drew my attention were the two excellent chest pockets. They are easily big enough to stow, phones, gloves, some food, a folded map or even a climbing guide. During the breezy, cooler spring climbing conditions the pockets have been great for stashing belay gloves and have worked perfectly when wearing a climbing harness. When hiking I’ve been able to pop my phone in one pocket and a folded map in the other. Again they work well and are accessible when wearing a hip belt on a pack, although there was some restriction when wearing a chest harness on a modern hiking pack. These chest pockets are finished with YKK reverse coil zips and rubberised tags that are glove-friendly. They are finished with storm flaps that help keep any rain showers from ingress and help keep the jacket’s silhouette when you are not using them.
The excellent chest pockets easily swallowed up thicker belay gloves in cooler conditions.
These aren’t the only pockets however, there are two zipped hand warmer pockets, I haven’t needed to use these at all and in my opinion are superfluous as the chest pockets are so good. I can understand that the designers would be reluctant to ditch these as it removes a little versatility. They are finished with YKK zips and the same rubberised tags. The flat nature of the pockets means I haven’t noticed them when wearing a harness or pack hip belt. For the weight why not have the extra pockets – some people find them useful. Another added bonus of the four pockets is that the front of the jacket is fully lined with mesh, which is useful for both wicking moisture and retained heat – a well thought out feature.
The chest pockets were a little more restricted when wearing a pack with a modern chest harness.
The main fabric of the shell is the lightweight Fortius 1.0 fabric, it’s super stretchy, offers good breathability and is windproof in most 3 season conditions. I’ve been wearing it with either a thin basleyer or t-shirt in warmer conditions and it’s been comfortable to wear: breathable on the approach, and comfortable for breezy hiking and cycling. I don’t think I’ll be wearing it for thrutchy style trad climbing but for sport climbing it’s been great and for general mountaineering it has performed well. The shell would have been designated AR, for those who remember AR stands for All Round, and I think that’s a fair reflection on the way the jacket performs.
The DWR works well enough for an unplanned, light shower but for anything other than that you should expect water to leak in after 20-30 minutes. To be fair, I have never had a DWR treated jacket that hasn’t wetted out eventually, It’s all well and good having a bucket of water thrown over your head on TikTok but running or hiking around the Lake District mountains in driving rain will see any DWR fail in pretty short time. That said this version of the Gamma range has worked fine in light showers.
I have been testing a size Medium, this is my usual size in Arc’teryx jackets and always has been. The fit of the Gamma Lightweight Jacket feels boxy, I’m unsure whether this is just the trend for a boxy silhouette or the sizing is off. I feel I could have gotten away with a size Small (which would have boosted my ego no end😉). The style is Relaxed Fit for this jacket and for the types of activity it is designed for I would have expected a more performance style of fit. I mean, it hasn’t felt massive and I suppose it means I can wear thicker layers when the temperature drops but I’ve found the sleeves flap around a little when the wind gets up. Also the sleeves have a half elasticated cuff, I’ve noticed this more and more on jackets in the last few years as designers have removed the hook and loop adjusters on cuffs. I can understand that it saves weight (in a sport where weight rules) and that it can be easier to deploy when wearing gloves, but it does assume that everyone is the standard 6 foot model in size – if only I were, my climbing life would have been so much easier! This means that I’m going to have to spend a little money on getting the sleeves professionally altered – fully elasticated, or even better lightweight hook and loop closures would have been perfect.
The Gamma Lightweight Jacket is finished with a full length YKK reverse coil body zip which has a laminated storm flap inside to help keep water and wind out. A well sized collar, double-sided hem adjusters to help trap in the heat, bartacking on stress points and a discreet, reflective Arc’teryx fossil logo on the chest. It also has a UPF of 40+ rating so is suitable for use in full sun.
In conclusion, the Arc’teryx Gamma Lighweight Jacket is a great addition to an iconic range of jackets. It is remarkably versatile and will perform on the crag as well as on the hill. On top of that it looks good enough for wearing to the office, campus or pub. It has some nice features and the premium fabrics enhance the usual Arc’teryx touch. It’s not a ‘one jacket to rule them all’ type of item, although for 3 season activities it is, but you will find yourself wearing it very often indeed, probably all the time.
The Arcteryx Gamma Lighweight Jacket comes in sizes XS-XXL and four colour options.
The SRP is £220 and it is available direct from Arc’teryx UK.
The female specific version is the Gamma Lightweight Hoody which comes in sizes XXS – XXL and five colour options. The SRP is £240 and it can be bought directly from Arc’teryx UK.
Disclosure – CGR reviewers and writers are never paid to provide a review and the website does not take advertising or link to affiliate sales. We are a bunch of keen climbers and travellers who accept sample products and offer an honest and independent review of the item.
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