I'm a recent buyer of a Stevens 200 who also decided to do something about its trigger pull of 8+ lbs. I too, googled adjusting Stevens 200 trigger. Of course, I found adjusting the set screw on the end of the straight trigger spring and posts about replaceing the straight trigger spring with piano wire/music wire and such. To answer your question, music wire is wire in pianos and such. Did you see a post about use of a spring made from a safety pin? Anyway, having no piano wire, I decided to just thin out the factory spring along its area that rests on the catch between the ends of the spring. Except for bottom area of spring that rests on catch, I thinned rest of diameter of spring. Slight metal removal with use of my bench belt sander and then additional thinning with 220 grit sandpaper. Just a guess, removed 20% of metal along 3/4 inch of spring. So, between adjusting set screw and my thinning, got trigger pull down to 3-4 lbs. Hardly a bench rest trigger pull now, but acceptable to me, even though I don't hunt and shoot from bench one day a week at range. My Stevens rifle now easily capable of 1" or less 100 yard groups. Much less, when I do my job and have right hand loads. Somewhere I saw a post proclaiming, "Don't lower Stevens 200 factory trigger below 4 Lbs", reason, safety problems then possible with closing bolt and trigger accidentally being released and etc.