a friend and i were at the range and met this guy who was shooting his ar, it was all tricked out. on his fire selector switch was this thing that when you pushed it forward it made the trigger pull really light, he told us what it was called but we cant remember what it was. it was just like any other fire selector switch with a safe, fire selection but if you pushed it forward past the fire position it set the trigger so that it was really light. does anyone know what this might have been?
Mechanically, I can't see how it would do that unless it actually lifts the trigger assembly so that it disengages the sear halfway, but that's ridiculously unsafe.
This is assuming stock trigger geometry. If he has a whole new fire control group, then it would be possible. Generally this kind of arrangement is known as a set trigger.
However, for an AR, unless it's a complete precision build, there's no need for a set trigger, a light pull trigger by Timney, Jard or any of the other name brands are just good. And in my opinion, I would trust it more.
There are several companies that make set triggers for AR15s but as stated before I would question putting one into an AR where your making it half assed hybrid trigger in a platform that was not designed for it. If you want a better trigger for a precision build just get a match trigger from timmney, Geissele etc.
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