In August 1848 not only the well known Tannenberg handgonnes were exavated from a water cisterne at Tanneberg Castle (Hesse, Germany) but also an iron ramrod lying near the handgonnes. The find can be securely dated to 1399 when Tannenberg Caste was sieged and destroyed by the City of Frankfurt. The find is publised in J. von Hefner, J. W. Wolf: Die Burg Trannenberg und ihre Ausgrabungen. Schwerberg, Frankfurt 1850 Online
. On table VII the ramrod is marked with a "D" and here you can see its dimentsions compared to the handgonne. Till yet I don't know where the ramrod is kept or if it is still survived after the excavations some 160 year ago. The handgonne is kept at Germanisches Nationalmuseum in Nuremberg and I hope so the ramrod too.