All: Krupp laufstahl is not coarse steel but means barrel steel. Lauf is the German word for barrel. The latch on the side is a Greener side safety - common on drillings and combination guns but uncommon on bolt action rifles.
The African model that Speed refers to is an original Mauser factory sporting rifle model. The original Mauser African Model is very rare. Your rifle, on the other hand, was built by an individual gunmaker and is perhaps even rarer than the Mauser offering but will not command anywhere near the price that a Mauser African Model would command. Still, it is a very nice piece that should be quite desirable among Mauser buffs.
The rifle appears to be a wonderful example of a pre-war product of a fine custom maker in Germany.
Tom
