"Sturmgewehr" does not simply equate with "automatic weapon".
According to Wikipedia, the term "Sturmgewehr" (StGw) refers to relatively light and compact multi-purpose military weapons, which are, technically speaking,machine carabines. These generally refer to semi-automatic and fully-automatic weapons. Check the reference:
English: "Assault rifle" - which is referred to as "a selective fire (selective between semi-automatic, automatic and/or burst fire) rifle that uses an intermediate cartridge and a detachable magazine".