This article is pend with 30 round aluminum USGI AR-15/M-16/M-4 magazines in mind, but it can be made to work for most any magazine.
For a more professional look, check out magpul.com
Step 1: What you need
2. Paracord, aka 550 cord. 6"-6.5" per magazine
3. 100mph tape, duck tape works to, gaff doesn't hold up well.
4. A cutting tool. for paracord.
4. FIRE! lighter works just fine.
Step 2: Prep
Pic2. Cut 6" to 6.5" of paracord.
Pic3. Melt the ends of the paracord with the lighter. Because the paracord is made of nylon (a form of plastic) it melts (rather than burns) when exposed to flame. Hold the flame to the paracord until a decent blob of molten plastic forms. Remove fire and allow to cool for a few moments.
Step 3: Attach
Pic2. Cover with tape.
Pic3. Loop paracord over the bottom of the magazine, cover with tape to form the loop. I like the loops on my mags to be of a decent size, so no matter what gloves I am wearing, I can still "hook" the loop and pull the mag free of the mag pouch.
Wrap the mag with the 100mph tape a couple of times, not to much, or the mag will be fat, and even tigher in the mag pouch, but not so little that you pull the paracord out instead of the mag.
Pic4. Make sure the blob of melted paracord sits outside the tape, acting sorta like an anchor.
Pic5. Finished product.
Look at you with your fancy high-speed-low-drag home made mag puls. Time to kick ass and chew bubble gum, to bad we're all out of gum.