I know you like to tinker with stuff and figure out how to make it work/shoot better but from here a new CZ .22 is looking like a good idea.
We were typing at the same time. I agree with this, pending 4" groups again on Tuesday morning. I'm out of ideas and don't know what I'm looking at with the borescope.
About your barrel, I have been totally confused as to why the roughest machined barrel I have--the P-10F--is one of if not the best shooter, tied with the pitted P-09 barrel. I'm to the point now where if I don't see a boulder in a groove that would gouge a bullet and cause a leak, I don't worry about what I see. I look for an irregularity like a single leaded groove that is only leaded near the chamber end, something like that. Machine marks apparently don't make any difference as long as they are uniform around the bore.
My mistake was shooting my friend's MTR at the range last week, using his scope eye relief, his trigger, his cheek weld, his focus, his level, his ammo, and shooting about a 3/4" group immediately.
I'll probably place my order on Wednesday, again, assuming poor results on Tuesday. I'm fine with admitting to a poor cleaning job prior to today if the gun can deliver several 1-1.5" groups in a row. Every accessory I have will go straight to the MTR from the Savage starting Tuesday evening if it get anything like I had on Friday.
Joe