I am working on a buddies 300 right now tat has the exact same problem.... Have changed scopes and put know tack driving scopes on it . Have shot factory loads and hand loads(300-400 combined) but to no avail. Checking the the stock for pressure points next and if that s not it gonna loosen the barrel and Re-headspace it.
If someone finds a solution please post... I have been building and rebarreling savages for years and this is the first out of the box that I have ssen that wont shoot.