my refurb 91/30 has the same marking in the same place on the stock it also bears it on the barrel shank (1943 izhevsk in postwar stock) . there was a good thread on the subject awhile back but i seem to recall that the general consensus was that it is a refurb facility mark and some documentation surfaced to suggest that /25\ was at izhevsk. it is still unknown where /12\ was