Weird problem.
Was this stock bedded to this action?
Was the recoil lug replaced with an aftermarket? If so, was material removed from the recoil lug area? Sounds like the front of the action is higher than it should be, not allowing the action to set in the stock level.
With a sharpie, color the bottom and all sides of the recoil lug and install the action into the stock. Remove and check for contact.
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