Abstract: A light armor piercing weapon, which is hand carried by a single man, is provided for firing or launching armor piercing rocket propelled projectiles. A propellent pack is worn or carried by the soldier along with a launching rifle. Unsymmetrical dimethylhydrazine is provided as a propellent and inhibited red fuming nitric acid, Type IIIa, is provided as an oxidant in a combustion chamber in the rifle. The explosive combination of the propellent and oxidant propels the projectile out of a smooth bore barrel and simultaneously ignites the solid propellent in the projectile. The projectile is provided with a disposable sabot which seals the projectile within the smooth bore. The projectile is provided from a spiral drum magazine which is gear driven by a mechanical coupling with a reciprocating breech block within the rifle. The reciprocating breech block in turn is gear driven by a gas driven piston communicated with the barrel.

Abstract: A silencer is provided for a machine pistol which silencer minimizes abrasive or frictional contact between the ballistic fired through the silencer in order to extend silencer life. The silencer includes a series concentric screen baffles which are retained in two concentric tubes. In the inner tube, a plurality resilient wipes are provided to contact the ballistic fired through the silencer without allowing contact between any of screen baffles in the fired ballistic.

Abstract: An automatic machine pistol is provided, which is not subject to fouling, which is compact and light while incorporating a pneumatic recoil buffer, which resists muzzle climb, and which can be accessed and cleaned without disassembly. The machine pistol is comprised of a reciprocating bolt within a housing of the pistol. The reciprocating bolt is carried within the housing on four rails by eight roller bearings. No sliding contact is made between the bolt and any other portion of the pistol. A portion of the high pressure gas from the barrel is bled through a bleed hole in the barrel block or barrel into a gas port tube which is telescopically inserted into the bolt. The gas port tube delivers the portion of the discharge gas in a forward direction in opposition to the motion on recoil. An upwardly directed nozzle is communicated to the receiving bore within the bolt.

Abstract: A bridge circuit for a measurement bridge of the type using four impedance arms provides an output referenced to ground which is a function of the impedances in the respective arms. The bridge circuit includes an impedance bridge comprising first, second, third and fourth impedance arms connected in series loop with first, second, third and fourth bridge terminals serially defined at the connections between the respective arms. A source of constant current is connected between the first terminal and ground. A driver is connected to bridge terminals other than the output terminal. The driver is responsive to bridge terminal signals to provide a bridge output which is a function of the impedances in the respective arms.

Abstract: A temperature compensated piezoresistive transducer includes a silicon body having a major top surface and an under surface. The body has generally parallel spaced first and second elongate slots formed therein extending through said top and under surfaces to define a center portion between said slots and first and second outer portions at the outward edge of the respective slots. The center portion is adapted to receive pressure to be measured. The body has an additional slot extending through the top and bottom surfaces and extending around the first, second and center portions to define the outer periphery of a transducer membrane with portions of the body remaining to integrally support the membrane. Plural piezoresistive elements having elongate and transverse dimensions are formed on the membrane. The elements are arrayed to receive compressive and tensile stress when pressure is applied.

Abstract: An amplifier circuit and structure having high input impedance and having a return path for conducting amplifier DC leakage current. A common diode structure forms the return path and includes two diodes connected in series and connected in opposite conduction directions. The diode having a forward conduction direction which is in the opposite direction of the leakage current is provided with a reverse saturation current which is substantially greater than the leakage current of the amplifier. The amplifier is typically a P channel or N channel field effect transistor (FET) and the double diode structure is typically an NPN or PNP transistor.