Also called "Pace Counter beads", they're used to keep track of how far you've gone while doing land navigation. Great for Scouts, back-packers, people who like dangling bits of string with beads on it...
Step 1: What You Need
550 Cord: A staple of any soldier. I've heard it called "Parachute Cord" too. You can find a 50ft roll of it at any military surplus store for two or three dollars. You should be able to find it at a regular box store too.
Beads: Just about any type will do. I have yet to find the "official" shell-type beads anywhere, but it's not important; as long as they fit through the rope (some guys in my squad have cool-looking skull beads on theirs).
Matches: A lighter will work too. Anything that produces a small, fairly controlled flame. :)
Okay, now that you have that, let's get started!
Step 2: Preparation
Pull out the core. That's the white strings on the inside. This lets you compress the cord, which will be important when you're putting the beads on.
Make a loop in the middle. First, even up the loose ends. Refer to the second picture for how to make a loop knot. Make a small loop if you're going to put this around a shirt button; make a bigger one if you're going to loop it through your LCE/LBE.
Fuse the ends. Using a match or your lighter, wave the cord ends back and forth through the flame until they start turning black. Then quickly mash each end together (not with each other) so it's closed off.
Step 3: Adding Beads (Top Rung)
There are several ways to do this; here's my method...
First, put the bead through one end of the cord. Pull it an inch or two up the cord.
***(If you can't get it in, use scissors to cut the black melted part until you can. I suggest a slanted cut to make it easer)***
Get the second end stuck inside the bead. Unless you're really really lucky, you won't be able to just push it through. Soooo...
Use the match to push the second end the rest of the way. A tooth pick or needle will work too. Try to have the point hit the black melted part so you can push off it. You may have to cut the second end as well.
How many beads you put on this first part depends on how far you're planning on walking. In the Army, each of the top beads represent 1000 meters. You may use yards, feet, miles, gigawatts, or any other unit.
Step 4: Adding Beads (Second Rung)
Next, add NINE beads. This is assuming you're using a system based on ten. When we're doing land nav, we pull one bead down for every 100 meters we walk, until we hit 1000. If you're using this for counting something in base 12, 16, or whatever, you would use a different "count-up-to" number.
Finally, tie another knot in the cord. Leave an inch or two, same as before.
Congratulations! If you've been following along, you've just made your first set of Ranger beads. Now, how do you use them?
Step 5: Using Ranger Beads
First, find your pace count. For most people it's between 60 and 70 left steps for 100 meters. You can find out what yours is by measuring off the distance, then walk normally and count every time your left foot hits the ground (or right foot. It doesn't matter, just use the same foot each time).
Now, every time you walk that many steps, pull down one of the lower beads. Each one stands for 100 meters you've walked.
When you've pulled all of those down, pull down one of the top ones AND push all the lower ones back up. This represents 1000 meters.
Repeat the process for however far you're going.
There you have it. Trust me, it'll make your life easier in the field, especially if you're sorta absent-minded like myself. Hope this was helpful!