Eprouvette

An Eprouvette is a one piece, fixed elevation mortar used to test the strength of gunpowder. It went out of general use by the middle of the 19th century. In use, a carefully weighed quantity of powder (charge) was placed inside, followed by a standard weight shot. The charge was fired and the distance the shot flew was measured and compared to the expected standard distance.

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 * Eprouvette Mortar