I was chatting to a German friend, partly in German and partly in English, with the aim of improving my German, when I asked her for a German equivalent of the English bog-standard, which means ordinary, run-of-the-mill, or nothing to write home about. The equivalent in German is 08/15 (pronounced as the separate numbers - Nullachtfünfzehn), as in "Dieses Verfahren ist 08/15" (This procedure is pretty standard/ordinary).
The term dates back to the First World War. The MG 08/15 was a particular model of a range of machine guns (see the English Wikipedia page). It was, seemingly, a clumsy and bulky weapon.
As for the origin of bog-standard, the OED says that there seems to be no connection with the meaning of bog as wet spongy ground. The most commonly held view is that bog-standard was a mishearing or misinterpretation of box-standard, which is defined in the OED when an adjective as 'In motoring, engineering, and other technical contexts: in standard manufactured form, unmodified; (hence) basic, unexceptional'. This usage comes from the noun, which is 'the main framework of a machine or engine'.