The main advantage of a smaller pack is that it's going to be packed more optimally most of the time and thus have better weight distribution. If 20% of the pack is empty, the weight will end up lower and further out from your spine than is optimal, making the pack more unwieldy and uncomfortable. This can be remedied some with tightening straps, but it's still not ideal. Just get the smaller one and practice packing more minimally.I like about a 80 Liter pack in summer, a 90L pack in the shoulder seasons and over 100 in winter. Mine is expandable from 75 to over 105 with attached PALS pouches. (MOLLE II and Pouch Attachment Ladder System) The larger packs give you some options that lower volume packs do not. Esp. in winter, fleece or pile insulation is more reliable than down but takes up a lot of room during the day since it does not compress well and you don't usually wear it while moving. In the summer, the higher volumes allow you to hike longer legs between resupplies, e.g., you can accommodate a 999 cubic inch 16" custom Bearikade bearcan.

If you get a down sleeping bag a bit wet or damp, you don't have to force it into a tight stuff bag. The ability to pack a down bag loosely means you lose less loft. You can travel with kids or family members who can't carry a full load. There's no need to have annoying hangers bouncing around - everything fits in the pack or in firmly-attached pouches.Trick 1 of a big pack is to avoid it going too high as it destabilizes you. (Most commercial high-volume packs go too high for my comfort). Trick 2 is to  avoid weight going too far back because it forces excessive forward lean to compensate for center of gravity problems. If you tend to carry some high-volume low-weight stuff (like fleece insulation, closed foam pad, down sleeping bag) it can occupy the rearward portions of the pack without causing too much forward lean. The Army settled on a high-volume design that keeps the weight quite low (below mid-neck level) by allowing it to go quite wide (when optional 15 Liter side pouches are added) and quite deep when the compression straps are loosened.

It compensates for the depth by having several features that allow the weight to be held tight to the spine -- though the volume can go quite far back as shown in the picture below. At some point, I'll get to old for this much pack, but I'm 67 and it still works well for me. I reviewed the pack at this linkReview MOLLE II for Sierra backpacking.pdfApart from the reason Robert Cezar Matei mentioned, I think another important reason to choose a small pack is to encourage yourself not to take too much with you. Packing too much is a mistake beginners very often make and it's often due to the fact that they can because their backpacks allow for it - but their physical condition often does not. I downsized myself from a 75 liter backpack to a 50 liter backpack for multi-day hikes in reasonable inhabited areas (meaning that I don't need to take supplies for more than a few days) and in not-too-cold weather and I found it to be very effective to force myself to pack less. I went from +15kg (that includes a 3kg. backpack) to about 10kg and sometimes even less (with a 1kg ultralight backpack).

Ip it's an old trail adage that if you have room you will fill it.I've somehow managed to do a 5 day winter ski mountaineering hut trip with a 45 litre bag, and yet in my youth I packed a 60lb 80L bag for three days. I would say you are doing things backwards. As you buy better lighter more pack able kits, it's generally ideal to start downsizing. 70L is what I tend to recomend to beginners. Lots of room to over stuff, make mistakes and take the kitchen sink.As you gain experience you quickly begin to learn that the experience of the trail is based very little on what you carry. ursuline backpackSo I generally see people coming into downsize as they learn to lighten their loads.ewok backpack disneylandUnless you are planning a much longer trip where you need to take a lot more food, I would endeavour to shave wieght and bulk. backpack tf soda popper

Dehydrate food, buy a lighter tent, jacket, insulation, sleeping bag, the works. Just work your way down. Mike Clellands excellent book on ultralight backpacking is well worth a look through. It has so many great tips for improving your hiking habits.Rucksacks are available in many sizes, each with a wide range of features designed to suit different purposes. In our How to Choose a Rucksack guide we will take you through the various sizes, common features and considerations you will need to make. supreme backpack 33rdThis guides aims to provide you with all the information you need to make an informed decision about which backpack is best for your needs.backpack osrs One of the main factors to consider when choosing a backpack or rucksack is what size rucksack/how big does it need to be. crumpler js backpack

This will depend on what you plan to use if for (eg. everyday bag or a week-long trip) and how much you need to take (the bare essentials or kit for an overnight stay). Is there a difference between a backpack and rucksack? In the UK a backpack (or daypack) will invariably be smaller and a rucksack will be larger. Both terms however are often used interchangeably. People often ask how big is a 65 litre rucksack? or how much can I fit in a 30 litre backpack? Backpacks are measured by the total capacity of all of the pockets in litres, essentially you will be able to fit in 30 litres of gear in a 30 litre backpack. This however might not mean a great deal when you are trying to decide if a rucksack is big or small enough for your needs. It is often easier to look at the actual measurements (perhaps even compare to a bag you already own) to get an idea of how big the backpack is. In this guide we will take you through the various backpack sizes and what activities and situations they are most suited to.

It is important that your backpack fits you correctly so you can carry it in comfort. This will depend on your build and back length (not your overall height). Most backpacks will come with adjustable back straps (bigger backpacks are also likely to have adjustable chest straps) to ensure your backpack fits securely and comfortably. If the backpack sits too low, even when adjusted, it is too big for you and vice versa. Check out our How to Fit a Rucksack guide for more information. Around 70% of the weight of the sack will sit on your hips. An adjustable hip belt is a common feature on medium and large backpacks as it helps to secure the bag around the hip area for added support and load transfer. Compression straps (adjustable straps which can be found on the top, side or down the front of backpacks) can be pulled tight to reduce the volume of the pack and to minimise movement of items within. Back & Chest Straps Adjustable straps are essential for ensuring a good fit.

Chest straps ensure the pack is secured and help distribute some of the weight of the pack. For larger rucksacks particularly you can adjust the height of the straps depending on the length of your back.  Often straps will be padded for added comfort- especially important for heavy packs. Multiple internal and externals pockets/compartments are useful for organising and separating contents. Internal security pockets are essential for stashing valuables whilst side mesh pockets are ideal for holding water bottles. Many of the Mountain Warehouse backpacks also have an MP3 player/Ipod pocket inside with an earphone outlet so you can listen to music easily on the move. To help divide contents further some larger packs may have a completely separate bottom compartment with zipped access that is closed inside with a drawstring. Larger rucksacks might also include hip belt and lid pockets for easy access to important or frequently used items. If you plan to wear your pack in the dark, on a night run or hike for example, reflective piping will help you be seen.

A rain cover (tucked away in a handy pocket) is useful for covering your rucksack to stop the contents getting wet in the rain. If your rucksack doesn’t come with a rain cover it is possible to buy rain covers separately. External Clips & Hooks External clips and hooks are useful for attaching gear you may need often to your backpack- especially useful for hikers and travellers. These include daisy chains (a strip of webbing loops), elasticated cords and walking pole hoops. Larger rucksacks may have internal frames to distribute the weight of the bag and support it on your hips as well helping your keep an upright walking posture. Mini and Small Backpacks – 6, 8 and 10 litre Small backpacks are very versatile and are as suited to shopping trips as they are for day trips or walks. An 8 or 10 litre pack will easily accommodate a packed lunch, drink and some packable waterproofs. The compact size also means they are great for kids. An 8 or 10 litre backpack makes the ideal school bag whilst our 6 litre backpacks (see our Mini Trek backpack) are the perfect size for younger children.

Mini backpacks are also popular with runners, cyclists and skiers as they are just the right size for stashing snacks and extra layers. (Please note it is not recommended that first time skiers/snowboarders wear a backpack as it can affect balance). Best For – Days out, Kids and Sports Not Suitable For – Carrying large heavy loads or for extended trips Daypacks – 10 – 30 Litres A daypack (or daysack) can be any size between 10 and 30 litres and as the name suggests they are primarily designed for one day trips. They are well suited to walkers and hikers who will be spending the day outdoors. Some daypacks will be hydration compatible so a hydration system can also be carried in the pack. A 30 litre backpack may also be suitable for weekend trips as it will easily accommodate spare clothing, water, food and other essentials. If however you have to take sleeping bags and other camping gear it is likely you will find the backpack to be too small. Smaller daypacks are also suitable school bags and are ideal for commuters.

Best For -Day walks, hikes and expeditions. Not Suitable For – Weekend trips that require you to carry sleeping bags and other camping gear. Medium Backpacks – 35- 50 Litres Medium sized rucksacks (often between 35 and 50 litres) are designed for multi-day use and for carrying heavier loads than daypacks. Most of these backpacks will have all the features of a daypack but with additional padding, pockets and fixing points for all the extra equipment you’ll need for a longer trip. A medium sized rucksack would be ideal for those thinking of an overnight trip. If you pack light a 40 or 50 litre pack would also be sufficient to hold your clothing, tent and sleeping bag for a 3 day hike. Best For – Overnight trips, 3 day hikes if packing light. Large Rucksacks – 65L + A large rucksack is ideal for anything from an extended hike (which will include camping) to travelling around the world. These rucksacks are designed to be able to hold a substantial amount of kit and will have plenty of pockets for storage.