An Improved Method of and Means for Testing the Accuracy of the Sights and the Bores of Guns.

摘要

13,571. Burns, W. A. June 9. Inspecting gun barrels. Relates to optical collimators for testing the alinement of gun barrels, and consists in arranging the collimator so as to be independent of, or merely supported by the gun barrel. The device comprises a convex lens A, Fig. 1, and cross wires B, or other object, at the focus of the lens, and may be mounted on a pivot X, and provided with a pointer D' moving against a scale E'. Micrometer-screw adjustments may be provided. Instead of tilting the whole collimator, the lens or the object may be moved laterally. The collimator may be carried by a rod fitting within the gun barrel or having flanges bearing against faces G2, Fig. 6, on the gun barrel. In the modification shown in Fig. 6, the line joining the lens A and the object B is at right-angles to the gun barrel, and the lens takes the form of a prism to turn the rays of light through a right-angle to a direction parallel with the gun barrel. The gun or the collimator may be mounted so as to be movable in a parallel direction. The muzzle and the breech end of the barrel may have plugs C2, C' with small central apertures to facilitate sighting therethrough.