This should be the last thing to be bought, however, I did not know this when I began purchasing my backpacking gear, and this turned out to be my first investment. I hated when I would go on the forums and bring this up and everyone would tell me that I should have not done so, but it was for the best. The rationale behind this strange theory is that you need to be sure that everything that you plan on carrying will fit inside the backpack. Obviously, you can’t know what size pack you need until you have all your stuff. Of course an argument to this is that “I will just get a big bag so I will be sure to have enough room.” Keep in mind that you have to carry that backpack with all that stuff inside it on our back. And you may even be a tough guy and can do it, but in the end it is wearing you down which makes it harder to enjoy the hike. One wise saying on getting bags big enough to fit everything, is that it will, and if you have room you will fill it with more stuff.
On the other end of that is the SULer’s (super ultra lighters). Some of these guys have a very minimal base weight (5 lbs or less). There are many different “weights” also. Base weights, dry weights, skin out weights, and total weights to name a few. While I don’t know all the different weights, this is what I go by:
- Base weight: Pack, shelter, and sleep system.
- Dry weight: Base weight + all other necessities minus food & water.
- Total weight: Exactly what it says.
So, back to the backpack. There are many types of backpacks with a lot of different names on them. Backpacks are measured by space, typically either by “xx” Liters or “xx” Cubic Inches. Here is a general guideline on sizes:
- Less than 3000 cubic inches: Ultra Light or Super Ultra Light
- 3000 – 4000 cubic inches: Light-weight
- 4000 – 5000 cubic inches: Mid-weight
- 5000 + cubic inches: Heavy-weight & Expedition weight
These are not definitive, and more so the way I would size them up. Also, there are different types of suspension systems to consider. Most of the larger packs use stays in the frame to provide even support, but not all. Some use hard plastic frame sheets, while others use none at all and rely on the users sleeping pad to provide the support (these are in the smaller packs). Some even use special suspensions such as carbon fiber hoops. The amount of suspension needed also depends on weight that will be carried.
Also, some packs allow parts such as the hip belt and the shoulder straps to be changed out for different sizes so that the packs will accommodate a large variety of users. Others use adjustable suspension systems that are able to be adjusted by moving the shoulder straps up and down on the pack to fit a variety of people.
Other than size of pack, the other important part of choosing a pack is fitting. First you need to measure our torso. You can have your torso measured at most outfitters, but if not able to do so you can do it yourself. You need to be able to do so correctly so that you get the right size pack. Here is how to do so according to ULA:
To accurately measure your torso length for a correct pack fit, grab a buddy and follow the steps below…
1- Standing upright, tilt your chin to your chest. Locate the largest lump on the back of your neck. This is your #7 vertebrae. It should be located close to the base of your neck proper.
2- From the #7 vertebrae, measure (with the flexible tape) down the length and natural curvature of your spine to the crest of your hipbones (iliac crest). This measurement in inches is your torso length.
There is a lot to learn about a pack. The best way to do so is by going and actually putting your hands on one and trying it on, with weight in it. Don’t be afraid to take all your stuff to a store and unload it inside a backpack and then walk around for 20 or 30 minutes. It’s best to find out how a pack fits before taking it out on the trail, and even more so before you buy it.