[Vehicles] Gunpowder Engines and Stirling Engines

[Varyon]

Originally Posted by Anthony

I suspect that depends on what you're using as an oxidizer. I can't find any evidence for smokeless powders (or, really, any conventional explosives at all) that beat the energy density of LOx/gasoline (it's significantly higher than octanitrocubane)

I came across a value of 11.3 MJ/kg (compared to the 10.4 MJ/kg you indicated for LOx/gasoline) here. The value is claimed to have come from this paper, but I can't access it to confirm.