Knew that was coming, just didn't know from who!
I adjusted the sear engagement last night, and it would still fail occasionally on bolt closure. I noticed the trigger shoe wasn't resetting itself if the muzzle was pointed upward, so I adjusted the trigger weight screw until it had a positive spring reset pressure. After doing that, all is good in the world. Just for reference, the Timney was 3 lbs out of the box, and is set at 5.5 lbs now. Still crisp and doesn't feel all that heavy, but it's safe.
Thanks again to everyone.
