GB1273036A - Obturators, particularly for wedge breech mechanisms of guns - Google Patents

Abstract

1,273,036. Gas checks and obturators. FRANCE ARMED FORCES MINISTER OF. 12 Aug., 1969 [22 Aug., 1968], No. 40370/69. Heading F3C. A gun having a wedge breech mechanism is provided with a metal obturator defining an annular cavity into which the gases created by the gun will pass, the obturator being in two annular parts one defining the outer side and a lateral sealing side of the obturator and the other the inner side through which the gases will pass. The rear face of the barrel 1 is drilled to define a cavity housing the obturator 2, the annular parts 4, 5 of which are of hard metal, such as gun steel. Adjacent the rear face of the barrel 1 is a breech-wedge 3 which forms a seal with the obturator 2. The external part 4 is deformed radially and slides axially under the pressure of the gases accompanying the departure of a projectile. This part is of angle section, the side perpendicular to the axis of the barrel 1 bearing on the front face of the breech wedge 3 and its side parallel to the axis being in contact with the wall of the cavity formed in the barrel. The internal part 5, which acts as a spring having very slight compression, also has an angle section. Passages 6 in the inner wall of the part 5 allow the passage of gases to the interior of the obturator. In an alternative construction, the obturator is fitted into the wedge and the arrangement is reversed, that side of the external part 4 which is perpendicular to the axis being in the plane of the breech face, whilst the purpose of each of the parts remains unchanged. In both cases, the assembly is designed and dimensioned in such a way that, when the breech block is in the closed position, in the static state, the axial bearing positions are assured elastically.