Just thought I would mention this since we are talking about AR triggers. I had originally purchased two Timney 3# Skeletonized Drop-In Triggers for my AR-15 and a family member's AR.
They both went in just fine. Everything was tight about them and the way they were installed. On mine, though, I would get intermittent extremely light hammer strikes to the point of no ignition. One such time, I had the crosshairs on a coyote in some personal woods. I had my ProEar electronic ear muffs on and I suddenly heard, to my left, panting! I looked over and there was a coyote, a good size one, standing there panting - no more than 18 feet away from me! He wasn't looking at me but must have smelled my scent and just stopped in his tracks). Anyway, I slowly raised the AR with Leupold Scope and aimed so the Barnes 62g Triple Shock bullet would enter between his eyes and run full-length through him. I carefully pulled the trigger and all I got was a very faint-sounding "click".
I was dumbfounded. I was fit to be tied. I am suddenly trying to rechamber another round (trying not to move and trying to still stay quiet). Needless to say, he saw me, turned and pranced through the woods as quiet as could be. I felt like taking the gun and wrapping it around the nearest tree (unloaded, of course)!
I got to doing research and later found out that many people have had problems with the AR-15 Timney Drop-in Trigger doing the exact same thing!
I got on the phone with Timney and, even though the triggers (mine and my relative's) were going on two years old (but hardly ever shot), they looked brand new. Timney offered to take them both back in exchange for two AR-10 Triggers which have a heavier hammer. The originals were 3# and these new ones are 4# and non-skeletonized. I could care less, so long as they work for us!
I guess that coyote was meant to live many more long, healthy days!
I got over it with Timney and still think very highly of them. I do recall that the rear pin holes (.154" comes to mind) did not quite line up perfectly, thus putting just a bit of an angled pressure on the pin where it went through the trigger housing. That would be the shaft that the trigger hammer pivots on and any binding of that particular shaft would reduce the energy of the hammer falling, slowing the hammer-drop just a bit, but enough to cause intermittent misfire!
The pins I used to replace the OEM pins have a small flat screw head on each end and I ground the length of the pins to fit perfectly with the two screws on each tightened. Then, when I was certain all was satisfactory, I put just a bit of Blue Loctite on the four screws for the two pins.
Everything is fine now and I still have high regard for Timney!
