7.62NATO
The constant is that after getting a good group, I removed my action from the stock. Can't change that. And let's say I cannot make it back to the range before opening day. If either of the following two scenarios occur, do you think I will be dealing with a change in POI?
1) My gun passes the dollar bill test. I remove it form the stock and see absolutely no signs of wear from the stock moving.
2) My gun FAILS the dollar bill test, and there are slight wear marks inside the stock. I install teflon shims per your example. Gun then passes the dollar bill test.
There is a possibility (IMO) that the POI
may shift just because your removed the stock or either of the two scenario's. How much that shift might be ???? It will probably be less by just by looking and putting the gun back together than anything. Even if you find polished marks in the barrel channel and then sanded them out - you still might get a POI shift.
If you shim it there might be a good deal of shift. But, once you have it shimmed it should be a lot more consistent.
Shims... the shims are only a temporary fix to the problem once you have the time you will end up fixing the entire problem by sanding out the barrel channel. And with the Omega stock it will need to be done at some point.
Bright side... Once you have it fixed it will all be good... and it will shoot very well.