This paper model is the Mortar Barge No. 10, created by PaperShipWright, and the scale is in 1:250.
The American Civil War saw the widespread use of large artillery pieces to attack fortifications. Mortar boats were one solution to the problem of getting the weapons to the places they were needed. Mortar Boat No. 10 was used by the Federal forces on the Mississippi and mounted a 12" mortar. ~ via Papershipwright
|20m||7m||70 tons||1 x 12-inch mortar||unknown|
|1:250||8cm/3cm||26||1 x A4||2/3|
You may get this papercraft model template here: American Civil War Mortar Barge No. 10 Free Ship Paper Model Download