I'll throw my opinion in here if anybody cares to hear it.
I like to see guys take a serious interest in learning more about their guns, by tweaking them here and there for better performance, accuracy, etc. That's how (most) of the master gunsmiths and custom gunmakers in the world today got started, and that's how they learned, whether we like to admit it or not. (And plenty of them ruined guns along the way, too.)
That said, most triggers are almost always in a gray area in that regard, and in my opinion, auto and semi-auto triggers are in a red zone. Don't go there unless you have a true professional gunsmith looking over your shoulder. It doesn't take a great deal of imagination to envision what could happen when a good trigger goes bad. And re-worked Mil-spec AR15 triggers usually go bad fairly quickly, (usually within a couple hundred rounds, depending on how deep the case-hardening is. It is usually VERY thin!)
A semi-auto going full auto on you in the wrong place and time can literally get you thrown into prison in this day and age. It happened to a guy here in Wisconsin recently.
I don't know the full story, but his (AR?) malfunctioned and fired a burst at the range. A couple cops saw it happen, and the last I heard, he was looking at 5-10 (?) in a penitentiary. I think he is serving time now, but am not current on the story.
Want a good trigger on your AR15?
Buy a Jewell, Timney, Giesselle, or any of several others.
(Dale is a pretty blunt fellow sometimes, but he is dead right on this one, in every respect he mentioned.)
BTW, I'm not harpin' on ya, SVT. I know your thread is well-intentioned and I might easily have posted a similar thread in past years, before age and experience had jaded me so...
Edited for spelling.
Edited by RONK - December/30/2009 at 19:22