The guns, ammo, and scenery are dieselpunk themed in that they appear post WW1. Examples of guns include the Mercury field gun which resembles the German flak 88, flak was developed in the inter-war years and stands for flugabwehrkanone (air defense cannon), and reliable flamethrowers and rockets weren't developed until WW2.
For ammo, lochnagar refers to a 25 ton mine placed under a German trench in the first war. The resulting crater was 140m across and 67m deep.
https://en.m.wikipedia.org/wiki/Lochnagar_mineIncendiary ammo was used in WW1 and proved highly effective against airships. Greased ammo was used in early submachine guns and designed for use on airship crews.
Kerosene and alcohol were used to power torpedoes. US servicemen aboard PT boats in the Pacific filtered the toxic alcohol mix into a drink resembling strong moonshine.
The battleships are post WW1 after the Dreadknot revolutionized battleship design. In WW2 the German Turpitz, the heaviest European battleship ever, was Churchill's biggest fear that tied up vast allied resources and lead to the greatest convoy disaster in history of arctic convoy PQ17. In 1942 Turpitz was relocated to it's base in the northern fjords of Norway. After damage from a British midget submarine raid the Turpitz was finally sunk by a 1944 air raid with special 12,000 pound "Tallboy" bombs. You can see the final resting place of the Turpitz in Northern Fjords