That sounds pretty odd. Seems like something isn't making proper contact. I'm glad you got some experienced hands on it to verify there's a problem.
I can tell you that if you return the rifle to Savage they will repair it and test fire it in their tunnel to make sure it is shooting well. That may be your best option at this point. Unfortunately, I don't think your efforts to find an accuracy load will bear any consistent fruit until you get this resolved.
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