Guest - Not logged in 

Reviews > Packs > Internal and External Framed Backpacks > Black Diamond Axiom 40 backpack > Test Report by Derek Hansen


Photo courtesy

Black Diamond — Axiom 40 Backpack

Test Series by Derek Hansen


NameDerek Hansen
Height5' 10" (1.78 m)
Weight175 lb (79 kg)
Email Address pix-obfuscated
City, State, CountryFlagstaff, Arizona, USA


I am a lightweight backpacker with a typical overnight pack weight of 15 lb (7 kg) and a multi-day weight of 20 lb (9 kg), which includes food and water. Because I pack less than 20 lb (9 kg), I prefer lightweight trail-running shoes. I prefer backpacking with a hammock as part of my sleep system.


Manufacturer Black Diamond
Year of Manufacture 2012, made in the Philippines
Manufacturer’s Website
MSRP $159.95 USD
Listed Features
  • reACTIV suspension with OpenAir backpanel
  • Top-loading roll-top closure with removable top pocket for quick and clean volume adjustment
  • Soft, breathable 3D mesh on hipbelt and shoulder straps
  • Trekking pole/ice axe loops
  • Dual hipbelt stash pockets, side stretch pockets and front compression stretch pocket
  • Hydration compatible
Manufacturer Recommendations

Hand wash in cold water with a mild detergent. Do not use bleach. Hang to dry.

Specifications What They Say What I Say
Weight (Large) 2 lbs 10 oz (1.2 kg) 2 lbs 14.65 oz (1.32 kg)
Volume (Large) 42 L (2,563 cu in) 42 L (2,563 cu in)
Colors Blue Steel, Coal
Sizes Medium, Large
Warranty Black Diamond Equipment, Ltd. offers a one year limited warranty to the original buyer for defects in materials and workmanship. Products will be repaired or replaced at the company's discretion.
Materials 210d Nylon Ripstop & Twill, 70 X 210d Dobby
Recommended Carry Weight Capacity Between 25 and 35 lbs (11 and 16 kg)


26 Mar 2012


The Black Diamond Axiom 40 backpack is a lightweight backpack suitable for multi-day backpacking trips. It is designed with a top-loading, central pocket with a roll-top buckle enclosure. There are two side stretch pockets that can accommodate 1L or smaller water bottles. An outer pocket on the back stretches and has side compression straps, but is open on top (there is no zipper or secure closing mechanism).


The pack features a removable floating lid with a zippered opening. Inside the floating lid is a plastic keychain clip.

Inside the main pack compartment is a hook-and-loop closure strap where a hydration bladder can be suspended. There is no hydration sleeve, but there is an elastic strap that keeps a hydration bladder from moving side-to-side.


The hip belt on the back features a unique "pulley" system to tighten the belt. By pulling outward, away from the body, the belt tightens. A small, zippered pocket is attached to each side of the hip belt. Near the base of the hip belt is the reACTIV suspension. The hip belt suspension system runs through a plastic sleeve at the base of the pack and attaches to both sides of the hip belt. In this way, the reACTIV suspension can be tightened or loosened to allow for more or less movement.

The pack has two axe loops where certain gear can be lashed such as trekking poles.

The back panel has a mesh fabric outer that covers a molded padding -- the Black Diamond "OpenAir" padding.

The sternum strap features one of my favorite built-in pack accessories: a whistle buckle.

Above the shoulder straps, the pack has top load lifters.



There's nothing like a new pack to get me salivating for backpacking, and the Black Diamond Axiom 40 has all the trimmings. The first thing that impressed me out of the box was how carefully the pack had been dressed for shipping. It reminded me of sitting down to an elaborately decorated dinner table, complete with intricately folded napkins and silverware laid out with precision. I was struck at how each strap had been carefully folded, wrapped, and tucked around the pack. Like a folded napkin, the effort seems so unnecessary and fleeting, but the attention-to-detail did not go unnoticed. Everything about the construction of the pack was top notch.

I've grown accustomed to smaller packs over the years as I've gravitated to lightweight backpacking. One detail that escaped me in the written material was the roll-top enclosure for the main pack compartment. Like top-of-the-line waterproof stuff sacks, the Axiom's main compartment has a long, tubular construction and the ends are fitted with plastic buckles and a stiff, plastic sheet to aid in rolling. The roll-top method means that I can easily adjust the volume of the pack as necessary for different types of trips. Also, I can remove the top lid and use the side compression straps to further reduce the pack's capacity. Unlike roll-top stuff sacks, the Axiom is not water proof, nor does it come with a pack cover, so extra care is needed to ensure my gear stays dry.

After unpacking the Axiom from the shipping box, I quickly stuffed it full of a typical overnight assortment of gear to see how it packs. As hoped, the pack swallowed the gear eagerly and still left me room for more. I noticed the pack had multiple side compression straps, and the webbing seemed excessively long. With a full pack and the compression straps taut, I found that the webbing was about twice as long as necessary. However, once I looked for a good spot for storing a basic sleeping pad, I soon realized that those overly long straps serve a good purpose: lashing on extra gear. The side straps, therefore, are just right for my large pad, and work great for smaller, self-inflating pads.

I next put together my typical assortment of 3-season backpacking gear and packed the Axiom again. This time, I also added three days worth of food and a larger hammock with a built-in bug net. The Axiom was unfazed with this new collection of gear and I found that I could probably squeeze in a few more items if necessary. The total weight was 15 lbs (6.8 kg), including the food and water.

The side pockets on the hip belt easily fit my compact digital camera, a compass, and a pair of glove liners and a small flashlight. The pockets would easily hold a small snack too.

I found the large outer stretch pocket sized just right to hold my map and waterproof case and my rain gear. With the compression straps loosened, I know I could also fit a wet tarp if needed.

pix-axiom-pack-list pix-15-lbs

The one area where I felt let down was the interior water bladder storage. Unlike other backpacks with sleeves or pockets for a water bladder, the Axiom only has an elastic strap and a hook-and-loop folding tab to hold a water sack. Unfortunately, I don't own any hydration systems that attach in this way so this part of the pack will probably miss out on a thorough test. The centered hydration tube opening is wide enough for a hydration hose. The pack's shoulder straps each have a small elastic loop near the top where the hydration tube can be secured.

One other disappointment, although minor, was that my 1L Nalgene water bottle popped out of the side stretch pocket when I leaned over to pick something up off the ground with the pack on my back. The pockets are just big enough to fit one of these bottles, but small enough that, with gravity's help, it popped out. The lower compression strap seems like it was designed to retain a water bottle, as one end is sewn under the stretch pocket. I like having my water bottles easily accessible when I hike, so I'll likely leave at least one bottle unhooked so I can reach and drink on the go. I'll monitor how well that works. I found that I could pretty easily reach back and grab the bottle and put it back when I was done.


I discovered that the inner frame of the Axiom is removable, at least most of it. Under the hydration strap is a pocket, secured with hook-and-loop fabric. There is a plastic frame sheet and an aluminum wire frame that are both held together at the top of the pack by two hook-and-loop straps. These two frames can be removed once the straps are unfastened. There is a lower section of the pack's frame that isn't removable as it is sewn into the pack.

I re-packed gear into the Axiom with the frame sheet and metal frame removed. The pack still rode well and held its shape. This is one place where I can save some weight, if I want. The metal and plastic frame weighed 6.4 oz (181.4 g).


Overall, I'm very excited to test this pack. I'll have to keep a watch out for my water bottle to make sure it doesn't jump ship, but I think overall it should be fine. The pack rides well and fits great.

PRO—Very spacious. Lightweight construction. Compressible. Comfortable.

CON—1L water bottle fell out of side stretch pocket when I bent over.


27 Jun 2012


I've been very fortunate to have several days and nights of backpacking in the past few months in a variety of conditions. In addition to the highlighted trips below, I've also taken the pack on a few day hikes in Flagstaff.

My pack weight averaged 18 lbs (8 kg) during most of my trips. However, when I hiked Humphrey's Peak, I had to carry a lot more water, which pushed my pack above 20 lbs (9 kg).

Apr 6-7: Fisher Point, near Flagstaff, Arizona. My son and I went on a backpacking trip to Fisher Point and had a blast! The overnight temperature was a cool 40°F (4°C) with the high during the day in the high 60s°F (15s°C). Elevation was 7,033 ft (2,144 m).

May 5-6: Flagstaff, Arizona. No moisture, just a hot, dry day in Flagstaff. The high temperature was 72°F (22°C) and the overnight low was 45°F (7°C). Elevation was 7,000 ft (2,130 m).

May 15-19: Damascus, Virginia. I participated in the Appalachian Trail Days and backpacked and camped along the Appalachian Trail every night (I only hiked about 2 miles (3 km) each day to return to town). I enjoyed the refreshing humidity and rain showers. Elevation was 2,400 ft (732 m).

May 24-26: Near Heber, Utah. Backpacked 4 mi (6 km) at an elevation of 8,000 ft (2,440 m). I experienced a wide-range of temperatures and conditions including rain, hail, deep fog, and sun. Temperatures ranged widely from near freezing to the 70s°F (20s°C).

Jun 22-23: Kachina Peaks Wilderness, Flagstaff, Arizona. I spent the weekend with Kurt backpacking the San Francisco Peaks. We hiked 26 mi (42 km). Elevation ranged from 8,000 ft (2,438 m) to 12,635 ft (3,851 m) at the summit. It was hot, dry, and very windy at the summit.


The Axiom pack has worked out very well so far and I'm very pleased with its performance. The pack really swallows my gear and I'm finding that I'm not filling it completely with my typical load. I'm a big fan of the roll-top enclosure for the main body.


Because the pack hasn't been completely "full", the top lid doesn't float on the top of the pack, but rather sags on the back. The lid's straps that connect near the shoulder straps can't fully tighten down with such a low volume so there is a little wiggle room.

The two side stretch pockets work great with 1L Nalgene (or similar) bottles, but during my hike on Humphreys I used the 2+L Platypus water bottles so I could bring more water. These larger water bottles fit fine and almost reach high enough to be secured by two sets of compression straps.

I pack my spare clothing and sleeping gear in the bottom of the pack with my hammock, tarp, and food placed on top. Most of my accessory gear is packed in the floating lid. The floating lid has proven large enough and handy enough for all of this extra gear. The zipper has functioned perfectly. I like that the zipper faces the shoulder straps as this tends to be the way the pack faces me when I set it down so the lid has been easy to access.

In the outer stretch pocket I've carried a map and also stuffed my rain gear, but it has been tough to really fit much more than that. The pocket does stretch a little, but it is fairly tight and I find that it isn't as convenient as the floating lid for most items I carry.

The pack carries my load very well. Even on the longer trek around Humphreys, I didn't mind the weight and I was able to carry the load evenly. I also was able to store my trekking poles on the pack for a few miles/kilometers. The loops and elastic holders worked great.


On two occasions, I've used the pack as insulation inside my hammock. While perhaps not ideal, I was very grateful for the extra insulation under my legs and the support it gave under my knees.


Overall, this pack has been great. If I have one complaint, it is that the large outer stretch pocket isn't very functional. I wish it were a little bigger (maybe gusseted), maybe with a zipper, or detached somewhat from the side compression straps.

I haven't had any of my Nalgene water bottles fall out. I noticed that the collapsible Platypus bottles seem to work better and fill the pockets better than the hard-sided bottles.


21 Aug 2012


I was able to take the Axiom pack on a week-long summer camp and a few overnight trips during this period.

Jul 15-20: Camp Geronimo, near Pine, Arizona. Summer camp with the Boy Scouts! I used the Axiom to pack my gear for this week-long camping trip. Thanks to the monsoon rain season, overnight temperature was a cool 40°F (4°C) with the high during the day in the high 60s°F (15s°C). Elevation was roughly 5,000 ft (1,500 m).

Aug 9-10, 17-18: Coconino National forest, near Flagstaff, Arizona. These were both family camping trips with minimal hiking, but I used the Axiom to pack all my gear. Elevation was 7,000 ft (2,100 m).


The Axiom pack has continued to be a great pack for me. I've been able to use it on more than just camping and backpacking trips; I've used it to shuttle gear around town and at work. I like how well it packs and so I've been using it nearly everywhere I need to tote gear around.

Carrying a load has been fine and comfortable. The shoulder straps and hip belt have worked comfortably, I just need to remember to loosen the hip belt before I release the buckle because it is more difficult to do so once the buckle is unclasped.

My typical pack method is to use the top lid to carry all my small, miscellaneous items like my first-aid kit, fire starters, hammock suspension, etc. It's been very useful. I use a large plastic garbage bag to line the pack and to waterproof my gear. I've noticed water leaking inside the pack (expected) so this tip has kept my gear dry.

I never got to use the minimal hydration system inside the pack. I do not own any compatible hydration bag, so I was limited to the outer pockets. These pockets continue to work fine, although I wish they were a little taller so that my 1L water bottles wouldn't pop out when I set the pack down (this happens if/when the pack falls over when I set it on the ground). Smaller bottles work fine and my larger 2+L collapsible water bottles also work great when inside the pockets and clipped behind the compression straps.

The only thing I wish is that the outer back stretch pouch had a better enclosure (zipper?), maybe gusseted (larger). I only pack a few things in that outer pouch because it is so tight and hard to fit bulky items inside.

Durability - While I haven't done any extreme bushwhacking with this pack, I have gone through a lot of brush and undergrowth, exposing this pack to potential rips and punctures. The pack has no visible scarring or punctures and looks in excellent condition. I haven't noticed any ripping, tearing, or loose threads on this pack. All-in-all, this is a very well-made pack and it has proven very durable.

PRO—Packs a large load very comfortably. The top lid is voluminous and holds a lot of gear.

CON—I wish the outer stretch pocket was more secure.

I would like to thank Black Diamond Equipment and for providing me with the opportunity to test this product.

Read more reviews of Black Diamond gear
Read more gear reviews by Derek Hansen

Reviews > Packs > Internal and External Framed Backpacks > Black Diamond Axiom 40 backpack > Test Report by Derek Hansen

Product tested and reviewed in each Formal Test Report has been provided free of charge by the manufacturer to Upon completion of the Test Series the writer is permitted to keep the product. Owner Reviews are based on product owned by the reviewer personally unless otherwise noted.

If you are an avid backpacker, we are always looking for enthusiastic, quality reviewers. Apply here to be a gear tester.

All material on this site is the exclusive property of
BackpackGearTest software copyright David Anderson