how do you tell a large shank savage from a small shank this is a model12 rb lp & do they come standard from factory with hs precision stock this is a6mmbr was looking at savage site the long range precesion shows it comes with hs precision stock but doesnt show chamberings in 6mmbr the model 12lrpv left port model 12shows it comes in 6mmbr but doesnt say hs precesion stock i surely do not want a tupperware stock hope someone can straighten me out on this regards shooter63.