CGPaul: I did not see this response until now. I'll definately put this on the to-do list.
I got up this morning and went down to the bench and started working through the suggestions.
1) The bore sighter showed the scope had not moved. I then rapped the scope in various places and looked again. Again, no change. My guess is the mount is ok. I did not change out the scope. However, it's a new scope. And the fact that the zero had stayed put indicates to me this is not the problem.
2) I checked the screws. 60 lbs on the front and just beyond hand-tight on the rear. I could still slip a bill down the outside of the barrel.
3) While I was putting the bore sighter away, I noticed the bullets out on the bench. I purchased these back in 2013 from Grafs. They're PRVI Partisan 175 grain PSP's. What caught my eye was that they're marked .322" . All other 8mm bullets are .323" I don't know if .001" is significant. However, I have since acquired some Hornady 170 grain IL RN's . I think I may cook up a batch of those and see if there is a difference.
4) I inspected the muzzle crown one more time. There's nothing there that looks obviously out of place.
5) In regards to M. Mule Deer's concerns, I gave the whole rifle a good shake from the rattle and tapped it gently with a used tomato stake, while commanding all demons within to depart. I then put it back in the rack next to the M1 Garand. Normally I keep these two rifles on opposite ends of the rack for obvious reasons. However, under the circumstances, I figure the commanding presence of the Garand will have positive effects.
