Just found this on this forum...
http://images.google.com/imgres?imgu...icial%26sa%3DN
"By the end of 1916 several wartime modifications had took place. A washer for protecting the firing pin whilst stripping the bolt was put into the butt, a grasping groove was put into the forend, only one lock-screw position instead of three was provided, finishing began to decline, cheaper woods, along with accelerated seasoning processes were introduced and some stocks had the lower butt dovetailed on from a seperate piece, so inferior stcok blanks could be used. Many were destroyed after the war. The few the Reichswher did keep had lange sights swapped for simple tangent leaf types ( now with minimum 100m sighting range ), the bolt handles turned down, their barrel bands revised and their designation changed to Karabiner 98b."
I wonder if there might be any answers there...