Can't answer your questions but I'll give you this. I have a bull barrel Marlin 7000 semi-auto that I like to play with once in a while; have done 1 MOA with it and I believe that it would do better with a proper bench rest and a scope that cost more than $30. That said, I have a book that says that a bolt action rifle can permit a tighter fit between the slug and the bore at the beginning of the barrel to more securely embed the slug into the rifling before firing which enhances accuracy. A semi-auto might not do this reliably among various brands of ammo so it must be looser as described to make sure that the round is fully in place. Will your bolt action choice be set up this way? I don't know.