Abstract: An improved gun barrel is disclosed in which the breech chamber has a length (B) and diameter (D.sub.2) which are chosen relative to the axial spacing (a) between a forward guiding ring (8) and a rearward driving band (6) of the ammunition unit to be fired from the barrel and relative to the diameters (d.sub.1 and d.sub.2) of the guiding ring and driving band, so that the longitudinal axis of the ammunition unit and the bore of the barrel are substantially aligned before the forward guiding ring enters the rifled portion of the bore.

Abstract: This invention relates to a device for use when evaluating optical signals by means of a chopper (2, 2'), i.e. a rotating shutter, and a photodetector (6, 6') for detecting the signal transmitted through the chopper (2, 2'). In order to improve the evaluation of the incident signal the opaque part (3, 3') of the chopper is provided with a reflective surface (7) to utilize also the optical signal falling on the opaque part (3, 3'). An additional photodetector (9, 9') has been arranged for detecting this reflected optical signal. In order to reduce the energy losses and in this way increase the amplification of the optical signal the device also comprises an optical element in the form of a glass prism (10, 10') in which one and the same surface is utilized both for transmitting and reflecting the optical signal.

Abstract: A full-caliber shell for training purposes to be fired with a low charge in a large-caliber firearm, e.g. a howitzer or a gun. THe shell comprises a front part (1) made of heavy material and an effect part casing (2) and a bottom unit (3) substantially made of plastic material which is highly resistant to high pressures. The effect part casing comprising the effect part and the bottom unit is arranged to withstand the great stress forces which arise in connection with the firing of the shell in the howitzer when the heavy front part is to be accelerated by means of said effect part and bottom unit. The stress forces are then very pronounced, and are of the magnitude of those arising in connection with the firing of a steel shell with the corresponding charge.

Abstract: One or more quartz tubes (1) are utilized in apparatus for the concentration of an acid. Each quartz tube is heated from the outside, and the acid is fed in at the upper part of each tube. Concentrated acid is drained off from the lower part of each tube into a vessel (3) and the vapors driven off from the acid during the concentrating rise inside each tube, and are led off from the upper part thereof. Inside each tube, the acid first passes through a rectification zone (A) in the upper part of the tube, and then passes through a liquid film zone and a reservoir zone.

Abstract: In an ammunition unit in the form of a shell (1), projectile or the like which is fin-stabilized, an extendable fin is utilized which is intended to be retracted during firing in a barrel or the like and to be extended as soon as the shell or the like has left the barrel. The extendable fin is intended to increase the stability of the ammunition unit in the ballistic trajectory. The extendable fin consists of two fin parts (4' and 4") supported separately in relation to each other and which in their extended positions are joined together and form the fin.

Abstract: A muzzle brake for artillery guns having a sidewardly open body attached to the muzzle of the barrel of gun. The body includes in a forward direction a front wall having a central opening for gun projectiles. The diameter of the opening being open to include an exchangeable wear ring attached to the front wall. The exchangeable wear ring is held in place by a plurality of locking devices. The wear ring is easily replaced and less expensive than a complete muzzle brake change.

Abstract: The invention relates to a fuze safety device (1) for an ammunition unit such as a projectile, shell, rocket or the like. The safe and armed conditions of the fuze safety device are defined by a movable slide or rotor member which takes a first position in safe condition and a second position in armed condition and cooperates with at least two locking elements (7, 8). Each locking element has its own condition for release and in their released positions they permit the movable member to assume its second position. The locking members (7, 8) are arranged to cooperate mutually in such a way that both of the locking elements are released when their release conditions occur in a first order but release of at least one of the locking elements is inhibited if release conditions occur in a second order.

Abstract: The invention deals with a filter for gas or liquid separation. The filter consists of a continuous fiber tissue within which a granular or powder formed (particle formed) activated material is contained (fixed). The activated material shall have the ability to absorb or chemically bind specific gas or liquid formed components. The fibre tissue is in itself sufficently porous to permit the said gas or liquid components to diffuse in through the same, while at the same time being sufficiently compact to keep the activated particle formed material fixed.The filter is primarily intended to be used in such a way that the flow of gas or liquid to be purified passes the fibre tissue in thin layers whereupon the relevant components can diffuse in through the pores of the fibre tissue in order to be bound or absorbed in the particle formed material.

Abstract: The invention deals with an impact igniter (1) for projectiles with a fuse (15) acting as a transport safety and delayed arming device. By partitioning off the fuse (15) and the striker pin (7, 17) located behind it forward in the projectile trajectory direction, and by leading some of the surrounding air which streams past the projectile, against the fuse (15) through channels (24, 31) angled in relation to the trajectory direction, the igniter has been made rain-safe without extending the arming time unacceptably.

Abstract: The invention deals with a method for temporarily eliminating those risks associated with transporting, storing and generally handling particle formed solid explosive substances. According to the invention this is achieved (desensitizing the explosive substance) by mixing the said explosive substance with a non-explosive substance which relative to the explosive substance is an inert particle formed solid material (desensitizing substance) having by and large the same particle size as that of the explosive substance. Salts, and in particular calcium chloride, containing chloride ions have been shown to be excellent as desensitizing substances. A mixture of trinitrobenzene (TNB) and calcium chloride (CaCl.sub.2) where the content of CaCl.sub.2 is greater than or equivalent to 55% by weight should not be classified as an explosive substance.

Abstract: The present invention relates to cast-loading of explosive charge compositions comprising at least two explosive components for cast-loading of a plurality of moulds or shell bodies (6) in a closed transportable unit (1). The moulds or shell bodies (6) are preheated to a predetermined temperature essentially corresponding to the melting temperature of the explosive charge composition. With the predetermined temperature substantially maintained the moulds or shell bodies (6) are filled with the liquid explosive charge composition after which a vibration movement of a specific frequency is imparted on the filled moulds or shell bodies by means of ball vibrators (24). Heavy particles of the explosive charge composition sink to the lower parts of the moulds or shell bodies. After a predetermined time period for sedimentation the filled and vibrated moulds or shell bodies are then cooled to a low temperature for solidification of the charges.

Abstract: This invention refers to a pyrotechnical delay charge, i.e. a pyrotechnical charge having a very well defined rate of burning. Similar delay charges are generally used in military fuses of various types. The delay charge according to the invention is distinguished by its components and their proportions relative to each other. Within the framework of the limits stated in the patent claims, the delay charges rate of burning can be varied from approximately 2 to approximately 30 mm/s. Characteristic for this delay charge is primarily that it contains more than 10% by weight tin dioxide (SnO.sub.2) which acts as an oxidizer and slag former.

Abstract: Nitration of aromatics wherein gasified aromatic compounds and nitric acid are contacted with a silicon-aluminum catalyst.