Abstract: To make a composite gun barrel, an inner barrel of a hard refractory material is formed and a composite jacket formed over it to increase the stiffness and strength while not adding excessive weight. The tows in the external jacket are varied in pitch along the barrel to decrease the amplitude of vibrations of a muzzle during firing. High thermal conductivity material is added to the resin to increase thermal conductivity. In the preferred embodiment, the thermally conductive material is chopped pitch-based carbon fibers and these are randomly oriented. A gas port is added and shielded from the composite material and a metal muzzle piece protects the composite from hot gases.

Abstract: A firearm assembly including a fluid deflector adapted to be connected to a discharge end of a barrel of a firearm, the fluid deflector including a first passage for flow therethrough of a fluid and a second passage in fluid communication with and angled with respect to the first passage for flow therethrough of the fluid.

Abstract: A composite barrel for a firearm comprising a substantially metallic liner and fiber reinforced resin, in which the fiber reinforced resin is under compression.

Abstract: A substantially nonbonded composite/metallic gun barrel is disclosed. The gun barrel has a metallic liner and a composite casing disposed thereabout. Unlike composite/metallic gun barrels of the prior art, the embodiments of the present invention provide little if any bonding between the composite casing and the metallic liner so as to decrease the warping of the gun barrel caused by the differing thermal expansion coefficients of the composite material and the metallic liner. In accordance with one aspect of the invention, a short binding layer is used to hold the composite casing to the metallic liner adjacent the chamber which holds a cartridge to be fired. The short layer prevents rotation of the casing and the liner with respect to one another, while preventing little risk of warping. In accordance with another aspect of the invention, a holding pin is inserted in the gun barrel to prevent the metallic liner and the composite casing from rotating relative one another.

Abstract: A composite/metallic gun barrel is disclosed having a metallic liner and alternating first and second groups of fibers wrapped about the liner, the first groups being disposed in a first orientation generally perpendicular to the long axis of the liner, and the second groups including one or more layers disposed generally parallel with the long axis of the metallic liner. By controlling the amount of fibers in each group relative to the other group, the coefficients of thermal expansion in the radial direction can be matched to provide a gun barrel having desirable firing characteristics.

Abstract: A substantially nonbonded composite/metallic gun barrel is disclosed. The gun barrel has a metallic liner and a composite casing disposed thereabout. Unlike composite/metallic gun barrels of the prior art, the embodiments of the present invention provide little if any bonding between the composite casing and the metallic liner so as to decrease the warping of the gun barrel caused by the differing thermal expansion coefficients of the composite material and the metallic liner. In accordance with one aspect of the invention, a short binding layer is used to hold the composite casing to the metallic liner adjacent the chamber which holds a cartridge to be fired. The short layer prevents rotation of the casing and the liner with respect to one another, while preventing little risk of warping. In accordance with another aspect of the invention, a holding pin is inserted in the gun barrel to prevent the metallic liner and the composite casing from rotating relative one another.

Abstract: A mortar design according to the present invention has been described. The mortar of the present invention weighs substantially less than the presently available mortars. Furthermore, the mortar of the present invention provides a dampening mechanism which substantially dampens the movement of the entire mortar assembly during firing of rounds.

Abstract: A motor case, including an aluminum barrel and a composite overwrap wound around the barrel to form a composite layer, which protects the operator against case failure during motor firing due to thermal effects caused by insulator defects or the like. The overwrap is formed of a fibrous material and a low temperature curable resin, the overwrap being mechanically bonded to the barrel. The method includes the steps of imparting texture to the outer surface of the barrel, wherein the textured surface includes jagged protrusions extending outwardly therefrom, wrapping an strip of fibrous material impregnated with a low temperature curable resin around the barrel, and curing the case.

Abstract: The disclosure relates to a method of producing rifled, non-metallic barrels of composite material in the form of a fiber-reinforced thermosetting matrix for rocket and grenade launcher ordnance, and barrels produced in accordance therewith. The characterizing feature of the present invention is that this results in barrels with the same fiber content in both the lands of the barrel rifling and in its rifling grooves which has been realized in that a porous fluffy mat with a high capacity to absorb the matrix material is employed in the rifled portion of the barrel.

Abstract: A composite electromagnetic barrel is preloaded to minimize rail separation by jacking the rails radially outwardly away from each other and wedging a pair of insulating members between the rails to retain the preload. The jacking force is then released.

Abstract: A venturi section or cone for a lightweight firearm such as a recoilles gun which is subjected to high transient pressures and temperatures on firing is formed from a resin impregnated multi-filament fiber material. The material in the form of an elongated tow is wound on a mandrel, cured, and then removed from the mandrel for subsequent operations such as machining or assembly. During manufacture, a hot gas erosion preventing layer is first formed on the mandrel and a plurality of layers of two are helically wound thereon at a helix angle selected to provide adequate axial and hoop strengths for resisting axial thrust and hoop loads produced on firing. Lightweight recoilless guns using such venturi cones are lighter and cheaper to fabricate than conventional guns and will fire more rounds before excessive erosion causes them to be unusable.

Abstract: A gun tube thermal shroud for reducing temperature gradients across the gun tube caused by asymmetric external and internal heat flux distributions, which includes an inner layer of high thermal conductivity extending about and along the gun tube in intimate thermal contact with the gun tube. In the preferred embodiment, this inner layer is formed of aluminum wire which is tightly wound about the gun tube and which is embedded in a thermally conductive flexible adhesive. The shroud also includes a middle layer of thermal insulating material and an outer layer of high thermal conductivity material, which may be formed in the same manner as the inner layer.

Abstract: A joint is provided for joining together two sections of a tube wherein the sections are prestressed by a surrounding pressure medium to press the sections together and to resist forces tending to separate the sections and the bursting pressure inside the tube. The pressure medium can be a resin which can be pressurized and subsequently cured or a fluid. The outside diameter of each section, at and near the end to be joined, is enlarged. A coupling means encircles the enlarged portions and couples the two sections together. One or more expandable pressure cavities located within said coupling means and/or within the enlarged portions have the general shape of a flared annuli. The pressure medium fills and expands the pressure cavities and, when pressurized, exerts stresses compressing both sections together at the joint and also applies relatively uniform radial stress in the vicinity of the end of each section.

Abstract: A gun barrel is constructed of an inner tubular liner of hard material forming the bore of the barrel and an outer jacket of carbon-fiber reinforced metal matrix material in which the fibers are helically wound about the liner. In a preferred construction the jacket includes an inner region, an intermediate region and an outer region in each of which the fibers have specified wrap angles and specified mechanical properties in order to provide high bursting strength, high torsional stiffness and high beam bending stiffness.

Abstract: A thermal protection device is intended for protecting structures submitted to high temperature and high speed ablative flow in the presence of high frequency vibrations and of the type comprising an armature containing a binder layer. The armature is a fringed meshing comprising a meshed portion submitted to ablative flow and fringes thereon directed to the structure surface to be protected with a predetermined orientation relative to the direction of said flow. Such a device is obtained for example by winding on a mandrel a fringed strip previously impregnated with a polymerizable resin which is polymerized after forming. The device can protect reactor conduits conveying high temperature corrosive gases.

Abstract: A barrel section for a lightweight firearm such as a recoilless gun which is subjected to extremely high transient internal pressures and temperatures on firing is formed from an epoxy-resin impregnated carbon fibre material. The material, in the form of an elongated tow is wound on a mandrel, cured and then removed from the mandrel for subsequent operations such as machining and assembly. During manufacture, a gas-erosion preventing layer is formed on the mandrel and a plurality of layers of tow are helically-wound thereon at a helix angle .theta.=tan.sup.-1 (.sigma..sub.axial /.sigma..sub.hoop) where .sigma..sub.axial and .sigma..sub.hoop are the axial and hoop stresses produced in the barrel section by axial and hoop loads respectively. Lightweight recoilless guns using barrels in accordance with the invention are lighter and less costly to fabricate than conventional guns and are capable of firing upwards of 30 rounds before excessive erosion causes the firearm to be unusable.

Abstract: A tubular structural element comprises a tubular body made of a fiber reinforced composite material having reinforcing fibers embedded in a matrix. The fibers are one of carbon, berylium, boron, glass, metallic or non-metallic, or a hybridized combination of the same. The tubular body has projections interiorly thereof which are integral therewith, and are of the same or another fiber reinforced composite material. The reinforcing fibers in the body are oriented in mutual stress transmitting relation, preferably circumferentially in the tubular body, and longitudinally in the interior projections. In making the tubular structural element, the fiber reinforced composite is introduced into each channel formed in a mandrel. The channels extend generally longitudinally of the mandrel, and optionally may also be spirally or helically oriented. Additional composite material is then overlaid generally circumferentially on the mandrel, to a desired thickness.