No confusion, I was referring to the .276 Rigby, which was the 7x57 Mauser iirc - that is why I wrote as such .276 (7mm) bring the bore measurement and .284" the 'normal' groove diameter when having standard 004" rifling depth.
|some rounds, on the other hand tend to have deeper rifling - as in some 9.3's and some .375's. Standard seems with euro rifles, to be .004" to .006" depth.