Dilemma solved
 

At the range earlier this week I was shooting my Savage Mark II 22LR. Being a safe gun handler I always have my muzzle pointed downrange and don't load the rifle until I am set on the bench. I was testing ammo for my Bergara but took the Savage along to shoot between groups with the Bergara. However I had a 3 instances where, while closing the bolt, the rifle discharged! I put the rifle up in its case and when I came home I did some inspection.
Taking the action out of the stock I adjusted and checked the trigger adjustment screws and cycled the action vigorously to be sure the sear remained engaged and all was fine. I put the action into the stock and tightened down the single screw that holds the action in place.
Cycling the bolt, the hammer dropped again!! I loosened the stock screw and cycled the action several times and it functioned as it should. This was the factory stock so I did some brainstorming and deciding what my next step would be before having to return the rifle to Savage.
I took a 1/16" washer and put it in a vise and gradually bent it to where it matched the barrel channel contour and set it in just ahead the chamber area. I put the action back in and tightened the action screw. I cycled the bolt numerous times as hard and fast as I could and didn't have a single failure. Great....but I don't want to leave a washer just lying in the barrel channel of the stock. So what to do? Bed the stock of course.
I took the action back out and liberally coated the section of the barrel and action with Johnson's paste wax and headed to the hardware store. I picked up a tube (double tube) of Devcon Plastic Steel Epoxy. Arriving back home I roughed up the area for the epoxy with some 50 grit sandpaper and wiped off the area with an alcohol rag to remove any dust. I didn't want to apply too much epoxy and only wanted a pad about 1"-2" so I took the previously used washer and slid it up the barrel channel to be out of the way of the epoxy but still act as a spacer to give me the correct pad height. I applied some more wax to the action and barrel, masked the stock to protect from overflow, and mixed the epoxy and placing it into the stock. I put the action in place and locked it down with the action screw.
I took the action out this morning and removed the spacer washer put the action back in and cycled the bolt and all is fine. Now I bet the rifle will shoot even better now the barrel is floating?!?!
The problem is that I don't know what caused this rifle to suddenly become unsafe?

It must not have the accutrigger?

No sir. I despise the Accutrigger. IMO that take up is ok for a handgun but not on a rifle. Give me the old fashion triggers that I can adjust to my liking without any creep and a crisp break.

This rifle in question although I solved the issue of premature discharge I discovered another issue. I had noticed earlier that there was,a notch cut out in the underside of the barrel and also in the stock there was a round hole about 5/8" in diameter.
i got on the Numrich Arms sight and looked at the schematic for the Ruger Mark II and I am missing a part that drops into that hole with a rectangular protrusion that engages the notch in the barrel acting as a sort of recoil lug. This part also, I assume, prevents the action from getting clamped too tight into stock which was causing the rifle to fire.
I called Savage and they're send me the part free of charge.