GB798352A - Improvements in or relating to an open-chamber gun - Google Patents

Abstract

798,352. Open-chamber guns. DARDICK CORPORATION. Aug. 27, 1956 [Sept. 27, 1955], No. 26180/56. Class 119 Relates to a gun with a rotary chamber drum 1 having spaced open chambers 2, 3, 4 each running from end-to-end of the drum and adapted to receive a cartridge case 15 whose outer surface forms a continuation of the cylindrical surface of the drum. According to the invention, the drum 1 is journalled in a rigid breech frame 5 having an upper rail 9 which is provided with a relatively slidable breech portion 16 of wedge formation adapted to span an open chamber from side-to-side and end-to-end. One surface 18 of the wedge 16 is concentric with and of the same radius of curvature as the drum and the other surface 20 is inclined to the surface 18 and is in sliding engagement with a complementary surface 21 of the top rail 9. The arrangement is such that after firing, when the case 15 has expanded into tight frictional engagement with the breech surface 18, rotation of the drum 1 in a clockwise direction will drag the wedge 16 to move it away from the case 15, thus eliminating the frictional drag of the case 15 on the breech at the very beginning of the rotation and freeing the case for easy ejection upon further rotation of the drum. Stops 22, 25 limit the movements of the wedge and a leaf spring 27 urges the wedge 16 to its starting position. The lower rail 10 of the stationary breech frame is similarly provided with a slidable wedge 17 in association with a second barrel 13, Fig. 1 (not shown) firing alternately with the first barrel 12. The invention is also applicable to guns having more than two barrels.