The impression I got was the firing pin wasn't getting to the primer until the bolt was lifted ever so slightly. I pulled the firing pin and saw nothing out of order...no grease or gum or small animals.

I guess my suspicion is the cocking piece is binding somehow? I'll play around some more and see where it leads.

Hoot,

Possible that someone has the overtravel adjusted just a skosh too snug. Back it off a turn and see if that helps. If it does, make sure all the trigger/sear giblets are clean and re-adjust.

Jimmy P.

Have not had that problem with an M77 before, wonder if the sear is being prevented from releasing the firing pin or if the firing pin is binding on something in the action?

Messing up the overtravel adjustment could produce what you are seeing. I think the more common goof is to adjust those triggers so light that the rifle fires when safety is disengaged, buttstock is bumped, etc.

But did have to fix a few model 721 rifles because the owners tried to make the safety easier to use and wound up making the rifle unsafe. The safety on these had to pull the firing pin out of engagement with the sear and required a fairly good amount of effort. Several people reduced the effort by lessening the contact of the safety and this allowed the firing pin to slip past the sear if the trigger was pulled while the safety was on. When the safety was later moved to the fire position it would release the firing pin and fire the rifle.

Have also had to fix the trigger adjustment on a Browning B-78 because the owner had tried to adjust it for a very light trigger pull and made it unreliable. Sometimes it would release the sear, but the firing pin would not fall all the way. Sometimes the firing pin would slip past the sear with a good jolt. Sometimes it actually worked the way it should. It was a rather simple job to adjust the trigger properly once the relationships between all the parts were understood, but it took a while to figure out.

These are just a couple examples I have seen of mis-adjusted safeties/triggers which caused similar problems. I have not had to work on Ruger M77 rifles too often, so do not have a great working knowledge of them, but will be most interested to read what you find out to be the problem.