Re: R700 Reveiver
The SS M700's we've been getting as of late have this goofball groove cut into the rear tang portion of the receiver. Makes bedding them nice a chore. To resolve it, I've been using silver solder to fill it in, then draw filing/sanding to blend it back to the bottom of the action.
Not sure why Remmy is doing this other than maybe as a simple way to distinguish the two materials during production.
Beyond that there's no real advantage other than corrosion tolerance.
C.