Resourcefulness and logic.
The day before yesterday, I was presented with a gentleman's Norinco AK of some variety. The gun wasn't the point of interest; it was the recoil spring. It had come apart and no effort so far had gotten it back together, and the owner was convinced that the spring retainer was broken.
Ah, not so. I looked at the retainer (a twisted metal wire oval about 1/8" wide and 6" long or so) and noted that the open end was cut, not broken. "Ok, so I have all the parts here, how does this work..."
I tried looking at the other AKs in the store but the only one left was an Arsenal and it uses a solid metal retainer. No go.
Poking around, I noticed that when the two sides of the open end butted together, it was too wide to go through the spring. Aha! The little metal clip held the two ends together and nestled in the end of the spring... That's how it goes!
But, getting the retainer through the spring was fruitless, it snagged. How to avoid snags?
I overlapped the ends and wrapped it with scotch tape. Much less snagless now, but it still binds. So, I tied a string to it. But how to get the string to drop through the spring? Another strip of scotch tape, this time wrapped around the end of the string as a weight. Viola! It comes through!
At that point I bundled as much spring up on the main part of the spring guide and had a third hand pull the string till the end of the loose part of the guide was out. Then I simply stripped the tape off, put the clip on the end and gently let the spring out to it. Success!
Guy left happy, I was ecstatic (it was like solving a puzzle or playing a game to me, and I won), and there's another functional weapon "on the streets".
*That* is why I like guns.