176 results about "Carbine" patented technology

An indirect gas operating system for an M4 type automatic or semi-automatic firearm. The indirect gas operating system has a gas block having a cylinder. The gas block is fitted to a barrel assembly having a bore with the cylinder in communication with the bore. A piston having a piston end and a striking end has the piston end fitted to the cylinder. A bolt assembly having a striking surface is provided. When a cartridge is fired, gas displaces the piston end and causes the striking end to strike the striking surface displacing the bolt assembly. The cylinder and the piston are together removable as an assembly from the firearm without removal of the gas block.

An assembly for modifying an automatic firearm such as a carbine rifle to relocate operation of the firearm charge handle. The assembly includes a fore-grip bracket, a drive rod movable in the foregrip bracket and attached to the charging handle release lever, and a cocking handle attached to the drive rod, the rod being attached to the charge handle for alternately releasing and latching the charge handle for clearing the firearm. In one embodiment, the foregrip bracket is attached to a removable rail attached to the foregrip by a jaw type device. Another embodiment attaches to the foregrip by attaching the foregrip bracket by screws. Another embodiment attaches to a foregrip having no rail by means of a groove cut in the grip, having a pair of spaced apertures into which hooks of foregrip mount, the bracket being held in place by a rod receiver and rotatable latch.

A collapsible buttstock which is adapted primarily for use with military and tactical carbines, is supported by an extension tube which is connectable to the receiver of a carbine on which the collapsible buttstock is to be mounted. A storage enclosure is formed in the body of the buttstock and is sized and dimensioned so that it can receive a clip or magazine, typically able to carry 20 rounds, that is usable with the carbine on which the collapsible buttstock is mounted. The enclosure is provided with an openable cover that is hingably attached to the buttstock body. An easily operable cover latch assembly is usable to secure the cover in a closed position while facilitating expeditious opening of the cover to afford access to the spare magazine storage enclosure.

A lower sling attachment adapter for use in the M-16 rifle and M-4 carbine and their equivalents utilizing a rear or butt stock mounted on a tube, one end of which tube is threaded into the rear of the receiver of the weapon, the improvement comprising a lower sling attachment means mounted on said threaded tube near the receiver and having a hole through which the said threaded end of said tube is passed, said lower sling attachment means having sling mount means on at least one side thereof to which the lower end of a weapon sling is attached.

A closed bolt system with a trigger assembly for converting an open bolt, blowback type submachine gun into a single firing carbine is provided. The closed bolt system with trigger assembly includes a tensioned trigger member supporting a tensioned disconnector system. A tensioned sear interacts with the disconnector system and a tensioned hammer. The hammer strikes a firing pin in the bolt when it is released from the sear. The blowback of the bolt, as a result of expanding gases from the exploding and exiting round, re-cocks the hammer by re-engaging the sear with the hammer and disengages the sear from the disconnector system. Only after releasing the trigger will the sear re-engage with the disconnector system and thereby permit another round to be fired. A receiver having a cavity encloses the bolt and prohibits a fully automatic bolt to be used therewith.

A gun barrel handguard includes half sections having longitudinally spaced apart fins of plastic material positioned around the exterior of the gun barrel for absorbing heat but preventing it from being quickly transmitted to the exterior of the handguard.

A firearm interface for a buttstock and pistol grip that provides a means to attach a pistol grip or a buttstock assembly to a firearm, and shotguns in particular. It can be used for either modality individually or both in combination. It allows the utilization of an M16/M4 style pistol grip and the adjustable, as well as the fixed buttstocks of M4/M16 style rifles and carbines. The buttstock and pistol grip interface confers the ability to configure the firearm to different requirements and to the ergonometric needs of diverse individuals. By facilitating the use of M4/M16 style receiver extensions and M16/M4 style pistol grips the buttstock and pistol grip interface brings a vast array of options to the firearms to which it is afixed. For those individuals with military experience the use of M16/M4 style components imparts a degree of familiarity and utility.

The embodiments described herein relate generally to a sleeve piston for operating the bolt carrier of a firearm. The sleeve piston can comprise a monolithic sleeve piston or it can comprise two or more sleeve-piston parts, thereby evenly distributing the reciprocating mass of an auto-loading firearm about its barrel, minimizing muzzle rise. The sleeve piston can further be coupled to the bolt carrier by two or more operating rods, thereby reducing the tipping force or off-axis torque experienced by the bolt carrier during firearm operation. The sleeve piston can also reciprocate in a sleeve gas block coupled to a barrel, thereby helping to transfer heat away from the barrel. The sleeve piston embodiments of the present invention provide a balanced and compact operating mechanism that is ideally suited for rifles, carbines, and personal-defense weapons.

The invention provides a nanometer carbonized tungsten compound powder, which includes carbonized tungsten, vanadium carbide or/and chrome carbide, and a metallic element without binding phase exists in the compound powder. The preparation method of the nanometer carbonized tungsten compound powder is characterized in that the powdery ammonium tungstate, the carbonaceous reducing agent and the inhibitor are adopted as raw materials, the raw materials are dissolved in deionized water or distilled water and evenly stirred so as to obtain a solution, then the solution is heated and dried, the precursor powder is obtained finally, the precursor powder is put into a high-temperature reaction furnace, under the vacuum, argon or hydrogen atmosphere protection condition and the condition of 1,000 to 1,200 DEG C and 30 to 60 min, the carbonized tungsten compound powder with the average particle diameter less than 100 nm and even particle size distribution is obtained through carbonization. The method has the characteristics of low reaction temperature, short reaction time, low manufacturing cost, simple process and the like, which is suitable for the industrial production and used for the ultrafine hard alloy nanometer carbonized tungsten compound powder.

The invention provides a chiral center nitrogen heterocyclic carbine precursor salt with a quadrol skeleton, a synthetic method and application. The precursor salt has a structural formula shown in the specifications, and can be prepared from cheap and readily-available chiral substituted diamine as an initial raw material by three-step synthesis, well applied to a polarity inversion reaction of catalytic aldehyde compounds, and used for preparing chiral benzopyrone compounds.

The invention discloses a chiral 1,2-diamine compound and a preparation method and application thereof. The molecular structure general formula of the chiral 1,2-diamine compound is shown as the general formula (I) in the specification. The preparation method of the chiral 1,2-diamine compound comprises the steps that an amine compound A and a nitroolefin compound B are added to a reaction system containing an n-heterocyclic carbine catalyst, an alkali reagent, a proton additive and a dewatering reagent for reacting and other steps. The chiral 1,2-diamine compound comprises chiral quaternary carbon atoms containing electrondrawing groups and amino groups, and can be widely used for synthesizing drug intermediates, especially heterocyclic ring structure compounds, and preparing functional materials. The preparation method is simple in process and low in requirement for reaction conditions, the reaction process is safe and controllable, the atom utilization rate and production efficiency are high, meanwhile, the enantioselectivity of products is efficiently guaranteed, and the environment pollution pressure of the methodology is low through the introduction of the small organic molecule asymmetric catalysis concept.

The invention relates to the field of organic synthesis, and particularly relates to a preparation method and an application of a chiral hexahydroxy n-heterocyclic carbine precursor compound. The compound has a structure as shown in a formula (V) in descriptions. The chiral hexahydroxy n-heterocyclic carbine precursor compound can be used for catalyzing multiple chiral reactions such as an addition reaction of unsaturated esters, alpha,beta-unsaturated imine and diborane pinacol borate, or a condensation reaction of aldehyde and boric acid compounds or a reduction reaction of ketone and has relatively good catalytic efficiency and enantioselectivity. (imgfile='DDA0000462319780000011.T'IF wi='392 he='496'/).

The invention discloses a method for preparing methoxyphenylacetic acid by natural anethole; the natural anethole is taken as a raw material and generated into the anisicaldehyde by oxidation reaction, then anisic mandelic acid (salt) is generated by the insertion reaction of carbine; finally the methoxyphenylacetic acid is obtained by reduction. The method has the advantages of reproducible raw material, simple operation and high yield, etc.; furthermore, the method can prepare the methoxyphenylacetic acid which can replace the source of petrochemical industry.

The invention discloses a dual-core nickel cross-coupling reaction catalyst supported by N-heterocyclic carbine and a preparation method. Acetonitrile is taken as a solvent, N-heterocyclic carbine ligand and silver oxide in the molar ratio of 1: 3 to 1: 6 are added and stirred, the reaction is carried out for 10 to 15 hours away from light; Ni(DME)Cl2 or Ni(PPh3)2Cl2, Ni(DME)Cl2 or Ni(PPH3)2Cl2 and the N-heterocyclic carbine ligand in the molar ratio of 2: 1 to 3: 1 are added and filtered, the filtrate is condensed, ether is added for precipitation of yellow solids, the yellow solids are sequentially washed by ethanol and ether for 2 to 3 times, the acetonitrile is then used for dissolution, the ether is slowly added, and the dual-core nickel cross-coupling reaction catalyst supported by the N-heterocyclic carbine is obtained by crystallization. The novel dual-core nickel catalyst synthesized by the invention can play the synergy due to the shorter distance between two nickel atoms, the catalytic effect thereof is higher than the common palladium catalyst, thus having very ideal catalytic effect on chlorinated aryl compounds with cheap price and wide application prospect in fine chemical and pharmaceutical industries and being environment-friendly.

The invention discloses a method for preparing a pyrrolin derivative, and relates to a method for preparing the pyrrolin derivative by a one-pot process. The method comprises the following steps: taking beta, gamma-unsaturated-alpha-keto ester, amine, diazo compound, metallic Lewis acid catalyst and organic acid catalyst according to a molar ratio of 1 to 1.2 to 1.2 to 0.01 to 0.2; dissolving the amine, the beta, gamma-unsaturated-alpha-keto ester and the metallic Lewis acid catalyst in organic solvent together to form a reaction system, and dissolving the diazo compound in the organic solvent within 1 hour to form solution, dripping the solution into the reaction system, catalyzing the diazo compound by metallic Lewis acid to decompose and form metallic carbine through three-component cascade reaction, making amine ylide formed by the metallic carbine and amine in situ trapped by the beta, gamma-unsaturated-alpha-keto ester in a 1, 4-addition mode; and then carrying out water by a water segregator to obtain the corresponding pyrrolin derivative. The method has the advantages of high atom economy, high efficiency, high yield, and so on, and the operation is safe and simple. The pyrrolin derivative is widely applied in the field of medicine chemical engineering.