Gunnery. [f. CAST sb. + OFF.] The ‘twist’ of a gun-stock, the extent to which the stock is thrown laterally out of the line of the longitudinal axis of the barrel.

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1881.  Greener, Gun, 249. He adjusts the bend or crook of the gun, and the amount of cast-off. Ibid., 432. The object of the cast-off is to bring the centre of the barrels in a line with the shooter’s eye.

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