20 inch Peru Gun
Consider the following facts:
- Two 20-inch Rodman guns were emplaced at Fort Hamilton, New York.
- These were cast at the Fort Pitt Foundry.
- The original plans for the USS Puritan included 4 Dahlgren Guns with 20 inch bores.
- At least one of the Puritan guns was cast at the Fort Pitt Foundry, using the Rodman hollow-cast bore, water-cooled core technology.
- The Puritan was re-designed to use two 20 inch Dahgrens.
- A XX-inch Dahlgren shell gun was sold to Peru.
The speculation is that a 20 inch gun, cast at Fort Pitt Foundry in the shape of a Dahlgren Gun, but cast with Rodman technology, was the "20 inch Rodman" sold to Peru. Four XX-inch Dahlgren shell guns were cast by the Fort Pitt Foundry between 1864 and 1867. Three were accepted by the U.S. Navy, but saw no service. The fourth gun was sold to Peru. An additional question would be if all were cast using the Rodman technology. Pustelnik (talk) 12:24, 11 February 2010 (UTC)
20-inch Russian Gun
There was one 20-inch iron gun M1869 in Russia. It was cast at the Perm iron gun facktory using slightly modifyed Rodman technology also. This gun was made on the order of the Russian Navy and fired 314 shots during the tests but never saw service. Now this gun stand in the City of Perm, RU as a museum artefakt.
- Kneeland, Samuel, ed. (1867). The annual of scientific discovery, or, Year-book of facts in science and art. Boston, Massachusetts: Gould and Lincoln. p. 111.