Caseless ammunition refers to small arms ammunition that packages the primer, propellant and projectile together without a cartridge case. They are fired using either mechanical or electronic means to ignite the primer. This design has different characteristics compared to traditional modern metal-cased cartridges. It a subject of some debate as to whether ammunition where the "casing" is metallic but part of the projectile and fired along with it, such as the Volcanic Ball , Soviet VOG grenades and the rounds fired by the Ho autocannon should be considered caseless: usually the term is reserved for rounds that truly have no metallic casing.
Rounds with combustible cases eg paper cartridges are also typically discounted. More specifically, after ignition of the propellant charge 5, the pressure builds up in the chamber 3a and the seal 11 moves in two successive phases from its starting position shown in FIG. When the round is first fired, as shown in FIG. The axial resultant of the pressure forces also flattens the surface 13 of the seal 11 against the rear face 2a of the barrel thus absorbing the locking backlash elimination Jv between the breech block 3 and the barrel 2.
The chamber 3a is thus rendered perfectly gastight as soon as this pressure value is reached. The pressure reaches its maximum value, somewhere in the region of 5. The seal 11 slides and ensures the radial and axial sealing by the elastic deformation of the sealing element directly subjected to the effects of the combustive gases. After firing, the seal 11, the barrel 2 and the breech block 3 recover their respective positions as shown in FIG.
In a general manner, the axial sealing surface of the sealing element 12 of the seal 11 is restricted to a fairly thin crown, as this enables :. In a general manner, the fastening of the seal 11 may be envisaged at the rear of the barrel 2, rather than making it integral with the sliding breech block 3.
We claim: 1. A sealing device for sealing combustive gases of a caseless munition, said sealing device being mounted between a barrel and a firing chamber defined by a breech block of a weapon, said sealing device comprising: a ring-shaped sealing element having a first end defining a radially extending sealing surface for contacting a rear face of the barrel, and a second end having an outwardly facing axially extending lip surface for contacting an axially extending inner wall of the firing chamber;.
A sealing device according to claim 1, wherein the sealing device is slideably fastened in a floating manner between the barrel and the breech block so as to be axially movable under the effect of the combustive gases. A sealing device according to claim 1, further comprising a decompression cavity for the combustive gases defined between the sealing element, the cooling element and the connecting wall. A sealing device according to claim 1, wherein the cooling element comprises a shape that substantially conforms to a ring-shaped space between the rear face of the barrel and the breech block.
A sealing device according to claim 4, wherein the cooling element is fastened to the breech block by at least one connector slideably engaging an oblong opening arranged in a wall of the cooling element. A sealing device according to claim 5, wherein the connector is a screw having a head locked by the breech block and a shaft that engages in the opening of the cooling element.
A sealing device according to claim 1, wherein the sealing device comprises an elastically deformable material having high thermo-mechanical properties. A sealing device according to claim 7, wherein the sealing device comprises spring steel. A sealing device according to claim 7, the sealing device is mounted in a pretightened manner between the barrel and breech block. A sealing device for sealing combustive gases of a caseless munition, said sealing device being mounted between a barrel and a firing chamber defined by a breech block of a weapon, said sealing device comprising: a ring-shaped element having a first end defining a radially extending sealing surface for contacting a rear face of the barrel and a second end, opposite the first end, having an outwardly facing, axially extending lip surface for contacting an axially extending inner wall of the firing chamber;.
A sealing device mounted between a barrel and a breech block of a weapon, said sealing device comprising: a sealing element that contacts both a rear face of the barrel and an axially extending inner wall of the breech block; and. But the mechanism is as simple as a flat spring on the side of the bolt that will grip the rim of the cartridge to extract the case from the chamber. Also, the use of a simple blade of metal as part of the receiver kicks the case off of the bolt face, as the bolt travels back in the receiver.
Our understanding of firearms is progressive over the years to the point where we can develop a reliable rifle that can fire thousands of rounds without a single jam. A caseless firearm does not have a way to eject, or clear the chamber of a live round. It can be a potential danger when you have a failed primer, or when you need to make the firearm safe for transport, disassembly, and cleaning. In theory, caseless ammunition is operational and superior to cased ammo.
However, the difficulty is the fact that all firearms are a tightly integrated weapon system. The many attempts to popularize caseless ammunition are just the same as those of replacing steel cars with aluminum. It can work, but a single change in design and function affects everything about the system. The details require a redesign from the whiteboard up.
The first reason why caseless ammunition is not modern-day ammunition is that there are not so many standard caseless versions that have been commercially released. Also, the production of caseless ammo makes for a material challenge. It is near impossible to come up with an explosive that is stable under every conceivable situation. Bullets get dropped, abraded, shocked, crushed, burned, soaked, shot, overheated, and aged among other harsh treatments. It took hundreds of years for modern bullets to get to the point they are today and that is why they go off only as they are supposed to.
The second reason caseless ammunition is not a favorite is that the ammunition is in the gun. There are a lot of things that must happen in the correct sequence.
A mechanical system moves the ammo around and we know that metal-on-metal is more forgiving than metal-on-caseless.
Afterward, the explosion must happen in a controlled setting, with a sealed chamber as the explosion propagates. When using a telescoped caseless ammunition, the overall bullet is shorter because the round is surrounded by a propellant. The explosion must first start by pushing the bullet forward before the rest of the explosion finishes.
The explosion needs to be clean because any residue will foul up the mechanical parts. If this happens, it can make the stuff used to make the caseless material strong not to burn correctly in the brief explosion.
When using cased ammo it would normally seal against the various chamber parts making it a disposable, controlled environment for the explosion. Caseless ammo in the chamber is under direct exposure to every explosion.
And when the traditional case is ejected it takes lots of heat and soot along with it. The caseless ammo leaves all the heat and soot inside the mechanism. Caseless rounds are limited by the fact that the cartridge body is primarily a propellant, and structural properties are secondary to the combustion properties. The primary issue is one of extraction. While caseless ammunition eliminates the need to extract a fired case, unfired cases must be extracted in case of a misfire, or to unload the firearm.
In metallic cases, this ability is provided by a rim or extractor groove machined into the rear of the case. Even in completely plastic bodied cartridges, such as the Activ brand shotgun shells , a thin metal ring is molded into the rim to provide support for the extractor.
One of the first caseless firearm and ammunition systems produced was actually made by Daisy , the airgun maker, in Several assault rifles have used caseless ammunition. Although the rifle never entered full production, it went through a number of prototype stages as well as field testing before being put aside in favour of a more conventional firearm, the G36 , which was also cheaper.
The first commercial caseless rifle featuring electronic firing was the Voere VEC Military Wiki Explore. Popular pages. Project maintenance. Register Don't have an account? Caseless ammunition.
Edit source History Talk 0. Main article: List of caseless firearms. ISBN
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