550 cord was originally used for the rigging lines of Soldiers’ parachutes during WWII. The specific type of parachute cord use by the military (MIL-C-5040H Type III) has a minimum breaking weight of 550 pounds – hence the term 550 cord. The cord consists of an outer nylon shell which is rated at approximately 300 pounds and 7 individual strands inside the shell that are rated at approximately 35 pounds each. Each of the 7 strands are actually made up of braided yarns rated at 17.5 pounds each. The utility of 550 cord is endless because of all of these different components.
The smaller strands and yarns can be used for stitching clothing, tents, bags, or wounds, used as fishing line, triggers for snares/traps, and whatever other small jobs you may have. The outer shell can still be used for most of your heavier jobs such as lashing poles together for a shelter or raft, tying a knife to a stick for a makeshift spear, keeping your important items tied to your body to avoid losing them, and the list goes on. With knowledge of a few knots from the SAS Survival Guide, you can make just about anything you may need – slip knots, quick release knots, nets for fishing/trapping/hammocks, etc. There are also ways to make bracelets, lanyards, belts, etc. in order to keep any where from 6 – 100 feet of 550 cord on you at all times. You can even wrap some 550 cord around other survival items, like I did with my knife, to use in the case of an emergency.
With the popularity of 550 cord rising, many manufacturers are trying to cash in by making their own version. The worst offenders won’t even use real nylon and just have fibers stuffed inside the shell instead of individual strands. There are other versions, however, that even though they may not meet the military specifications, are still useful. For example, they may have only 4 individual strands, but the weight rating listed on the packaging is usually still accurate. The outer shells also come in a variety of colors – original olive drab, digital camo, black, bright orange, reflective, etc. Depending on your anticipated use, several different colors might be what you want. For example, bright orange could be used to tie down your shelter/tent so you can see it easier at night or wrapped around a stick that you can swing above your head for approaching rescuers to find you.
One last tip – always melt the ends of your chosen 550 cord when possible. Melting the ends prevents fraying and possibly loosing the strength and core of your 550 cord.