Forgot about the quick lock time, that certainly contributes to the "shootability" part of the accuracy. Remington also has (or at least had) the reputation for making some of the best factory barrels.
I'd guess that the receiver configuration is what contributes the most to it's mechanical accuracy. Big tubular receiver with only a small bit of metal removed for an ejection port and magazine inlet makes for a very stiff platform to hang a barrel from. Didn't the bench rest guys try to accomplish the same thing by sleeving certain actions? Also the Tikka is known for very consistent accuracy from factory rifles and it has the same general configuration of receiver - small ejection port and mag opening.
Can't prove it but that would be my take on it.
Gunnery, gunnery, gunnery.
Hit the target, all else is twaddle!
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