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Flight Piston Dimensions: An estimate for piston volume prior to rod extension is 0.5599π [1.08 in for depth and (1.44/2)2π = 0.5184π in2 for area]
Using this black powder calculator and plugging in a tube diameter of 1.44 in, a tube length of 1.08 in, and 1 g black powder, yields a pressure of 1101.82 psi.
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