How much should your BOB weigh? Packing a ruck which is 25% of your body weight is pure fantasy for anyone over age 40. More than 10% is fantasy for anyone over 50, with very few exceptions as age brings with it issues in trying to maintain physical conditioning. My planning standard (age 71) is 10 kilograms (22 pounds) for seven days. With modern lightweight backpacking gear it can be done. Your pack weight is determined by what you need your gear to do, and for how long? Basics are protection from "the elements and evil," hydration, navigation, communication, nutrition, health and medical. Survival instructor Mors Kochamski summarized it: “Sleep warm and dry at night, stay hydrated, and cure your ills.” You must also stay oriented in order to move safely within your environment. In the short term having adequate food aids both morale and mobility. It helps maintain warmth and provides energy for emergency exertion. Once you exceed the duration of your food supply, you require means to forage, fish, hunt or trap to sustain a long term food source. Your BOB should sustain you for 7 days in likely environments without having to fish, hunt or steal = 7 days, at 20degs F within 10kg+/- FOOD: Do the math. An average adult male needs 2000 calories per day for moderate activity. An average trail meal (Mountain House) is 125 calories per ounce. The chili mac meal is 139 cal/oz. So, 2000 calories X 7 days = 14,000 calories; 14,000 calories / 125 calories = 112 ounces; 112 ounces / 16 ounces = 7 lbs. Which works out to 1 lb (454g) of dry food per day. A Convenient Rule! The remaining weight to plan out is now 13 lbs. (5.9kg). To cook freeze dried or dehydrated food you need a 800mL pot to boil water. Add a compact stove and you can cook anywhere, even while evading. SOTO Windmaster, output 11,000 btu’s, 1-1/2 hours burn time per canister, boils a half liter with only 5 grams of fuel, enough to hydrate one military LRP-CW ration or commercial freeze-dried meal. The canister contains 110 grams of fuel, so can cook 22 meals (one extra in our scenario). Some people argue that gas canisters don’t work in cold, but they are quite OK to zero Degs. F. Below that, carry them close to your body, under the anorak and they still work! PACK: Most modern packs are too heavy with all their bells and whistles. The old US military ALICE frame pack weighs 3.5 lbs. Your BOB pack should not weight more than an ALICE. The mountaineering community is now producing packs weighing about a pound, which are waterproof, bombproof and expensive!. Google “Figure 4,” “Wild things,” “Cilo” and “Hyperlite” for examples. Take ¾ of an Army surplus closed cell foam pad to shape any pack. Then try it out, ditching the frame to save weight. You may not need it anymore. HYDRATION: Pack 2 liters of water = 4.4 lbs. Remaining weight to plan is now down to 9 lbs.(~4kg). You need the ability to purify many gallons/liters of water. Non-potable water requires proven modern solutions. Use either chlorine bleach containing 6% sodium hypochlorite 2 drops per liter, or Betadyne from your first aid kit, 6 drops per liter. Iodine crystals can purify thousands of liters of water and take up little space, and are your best choice in Third World environments, long range movements or trips of long duration. With your 2 liter water container, a pot to collect, melt and boil water in and your chemical purifier, hydration is not going to be a problem. SLEEPING WARM AND DRY: The most, simple, versatile method is the bag and bivy-sack combo. Use the closed cell foam pad in your pack to insulate yourself from the ground. I replaced my sleeping bag with a polyester fiberfil quilt rated to 25 F (-5C) to save weight and bulk. MUCH better than the old GI poncho liners! With the bivy, 20 F (-10C) is no problem. Layer for colder temps. Add a lightweight, ripstop nylon tarp or “basha” for overhead cover in woodlands, and as wind, rain and snow protection. In a pinch you can make do with just the bivvy and survive in temperate zones with just a silk, polypropylene or merino wool base layer, work layer of ripstop 60/40 (BDU), Goretex outer shell, knit wool watch cap, waxed canvas boney hat and gloves. A microfiber pullover is useful as an extra warming layer takes little space and weighs nothing. MED KIT: Most prepared med kits are too big and rarely used. The wilderness medical society reports the most common wilderness injuries every few years. # 1 Blisters, # 2 GI stuff/Diarrhea, # 3 small cuts on hands from knives # 4 forearm / wrist injuries from falls. Cover the basics; tummy, toes and tolerance (pain). Kit should be able to treat a major bleed (Israeli bandage and QuikClot Sport25), some small boo boo bandaging, tweezers, GI meds, Pain meds, Antibiotics, Allergy / Anaphylactic meds, Opthalmic ointment and if trained a 14 ga and NPA for good measure. http://theemtspot.com/2009/12/08/the-art...al-airway/ With needle / thread and duct tape, my med kit weighs 7 ounces. MISC: Hands free trail lighting (Petzl LED headlamp) and cordage are essential. My pack is currently 14 lbs 5 ounces (no food, full water, not counting my Airweight S&W Model 12 .38 in coat pocket) with the mentioned items. With food 20 plus pounds, with loaded 4-inch S&W Model 12 and extra rounds just over 22 lbs. I would like to get it to 20 lbs, but will settle for my original 10 kilo goal. Add a Leatherman or Gerber multitool and a sturdy, lightweight fixed blade knife, such as a 5-inch Mora on your belt, a mirrored orienteering compass, compact fishing kit, ferro rod and tinder in your pockets, you will be ready for most natural and man-made scenarios. PDW: Most preppers fixate on firearms and ammo to the extent that the weight and cube in carrying them gets in the way of basic preps. If not in a war zone or serious civil unrest environment where hostiles are looking to KILL you, you may not need a firearm at all. Avoid contact, practice stealthy movement and evade. My EDC firearm is an Airweight S&W Model 12 .38 Special which weighs a bit over a a pound. I carry five "full charge" wadcutters and one Speer shot load in the gun, and a Speed Strip with a similar reload in my pocket. In the BOB I keep a CountyComm zippered keycase with 24 more full-charge wadcutter rounds, which give the best performance in an Airweight revolver which does not see +P. If faced with multiple adversaries if you stand and fight you're never going to live long enough to shoot'em all, so keep moving, avoid contact, stay hidden.