6 inch/53 Marks 12,14,15,18 gun
6 inch/53 Marks 12,14,15,18 gun is a rifled breech loader or naval artillery.
Overview
American naval gun.
In detail
It is associated with United States.
Sources
Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.
reference work · Reputable secondary · Wikipedia
“6-inch/53-caliber gun”, English Wikipedia, consulted as further reading
Consult the sourcereference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q4641514: 6 inch/53 Marks 12,14,15,18 gun
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