Fuel propellant load cap

Abstract

The invention relates to a combustible propellant charge for ammunition discharged from a gun barrel, comprising cellulose, nitrocellulose, MO3 particles, where M = Mo and / or W, and cationic surfactant, wherein the average particle size d50 of the MO3 particles is 0.5 to 2.0 μm, the maximum particle size d100 of the MO3 particles is ≤ 20 μm, and the ratio of the average concentration of MO3 in wt% in a volume element of approximately 0.05 to 1.0 cm3 (cVE) at any desired point in the propellant charge and the total concentration of MO3 in wt% (ctot) in the propellant charge is cVE:ctot = 0.80-0 1.20.

Description

[0001] The present invention relates to a combustible propellant cartridge case with MoO 3 and / or WO 3 particles, a method for producing the combustible propellant cartridge case and a use of the combustible propellant cartridge case for firing ammunition.

[0002] When ammunition is fired from a gun barrel, the burning of the propellant powders creates high temperatures and pressures, which lead to severe wear on the gun barrels, especially with large-caliber projectiles such as those used for artillery guns and tanks.

[0003] To reduce wear, erosion-reducing additives, such as wax or paraffin, as described in DE 39 27 400 A1, can be added to the propellant powder or the combustible propellant cartridge enclosing the propellant powder.

[0004] EP 1 227 295 A1 describes how erosion-reducing additives can be added to a propellant charge sleeve in the form of oxides of rare earth elements or of one of the elements of the sixth subgroup of the periodic table or polyoxymethylene.

[0005] EP 1 647 538 A1 describes the addition of polyacetylene or a mixture of WO 3 or MoO 3 and CeO 2 or La 2 O 3 or Y 2 O 3 in the form of particles to a propellant charge sleeve to reduce erosion, wherein the average particle size is 1 to 10 µm and the maximum particle size is 30 µm.

[0006] Tungsten trioxide (WO3) and molybdenum trioxide (MoO3) can be added to the propellant cartridge case to reduce tube erosion and thus tube wear to a certain extent, presumably by trapping atomic hydrogen. However, the tube wear of this ammunition still requires improvement to reduce maintenance, increase the service life of the weapon barrels, and, in particular, improve firing accuracy, as an eroded barrel exhibits significantly reduced accuracy.

[0007] Therefore, an object of the invention is to reduce tube wear in ammunition that can be fired from a gun barrel, especially in artillery or tank barrels.

[0008] This problem is solved by a combustible propellant tube according to claim 1, a method for producing a combustible propellant tube according to claim 11, and a use of a combustible propellant tube according to claim 15. Further features, embodiments, and advantages will become apparent from the dependent claims and the description.

[0009] One aspect of the invention relates to a combustible propellant cartridge case for ammunition fired from a gun barrel, comprising Pulp, nitrocellulose, 5–10 wt% MO3 particles, based on the total weight of the propellant tube, where M = Mo and / or W, and 0.01–2 wt% cationic surfactant, based on the total weight of the propellant tube. where the mean particle size d 50 the MO 3 -Particle size 0.5 - 2.0 µm, the maximum particle size d 100 the MO 3 -particle ≤ 20 µm, and the quotient of the average MO 3 -Concentration in wt.% in a volume element of approximately 0.05 to 1.0 cm³ 3 (c VE ) at any point in the propellant cartridge case and the MO 3 -Total concentration in wt.% (c total ) in the propellant cartridge case c VE : c total = 0.80 - 1.20.

[0010] Another aspect of the invention relates to a method for manufacturing a combustible propellant cartridge case, comprising the steps (a) Preparation of a slurry of cellulose, nitrocellulose, MO 3 particles, where M = Mo and / or W, and cationic surfactant in water, (b) mixing the slurry, (c) dewatering the slurry on a sieve form to produce a raw felt, (d) pressing the raw felt and (e) drying to form a combustible propellant cartridge case.

[0011] According to the invention, MO3 particles are understood to be MoO3 particles (molybdenum trioxide particles) or WO3 particles (tungsten trioxide particles). WO3 particles are preferred.

[0012] Within the scope of the invention, it was found that prior art propellant cartridge cases with metal oxide particles such as MoO 3 or WO 3 particles exhibit strong concentration fluctuations of the metal oxides in the propellant cartridge case, and that this is at least one factor for the still excessively high tube wear after firing ammunition with corresponding propellant cartridge cases.

[0013] Surprisingly, the use of a cationic surfactant in the manufacturing process leads to a relatively uniform and small particle size of the MoO 3 and / or WO 3 particles and to a lower concentration variation of the MoO 3 and / or WO 3 in the combustible propellant cartridge case, thereby avoiding temperature and pressure spikes during firing and thus reducing tube wear.

[0014] Without being bound to this by the invention, it is assumed that the cationic surfactant, in conjunction with a relatively small particle size and narrow particle size distribution, counteracts sedimentation of the MoO₃ and WO₃ particles during the manufacturing process. This promotes, firstly, effective recrystallization of the MoO₃ and WO₃ in the pulp (slurry) and thus enables a relatively uniform particle size distribution. Secondly, the dispersive effect of the surfactant, i.e., keeping the MoO₃ and / or WO₃ particles in suspension, promotes the adhesion of the particles to the fibers of the nitrocellulose and the pulp, thereby preventing the MoO₃ and / or WO₃ particles from settling due to gravity. This results in less variation in the concentration of MoO₃ and / or WO₃ particles in the finished propellant cartridge case.This is particularly relevant for the MoO 3 and WO 3 particles used according to the invention, since the density of these substances is particularly high.

[0015] The particle size and particle size distribution are determined using laser diffraction in a wet measurement (Malvern system, Mastersizer E, wet measurement in water in a cuvette). This yields a particle size distribution curve. dx means that x volume percent of the particles have a diameter smaller than the specified value. For example, with a d50 value (mean particle size) of 1 µm, 50 vol% of the particles have a diameter ≤ 1 µm (micrometers). With a d100 value (maximum particle size) of 10 µm, 100 vol% of the particles have a diameter ≤ 10 µm.

[0016] For the purposes of this invention, a surfactant is understood to be a substance that is surface-active and thus reduces the surface tension of a liquid or the interfacial tension between two phases, thereby promoting the formation of dispersions such as suspensions. Cationic surfactants have positively charged groups, such as quaternary ammonium groups.

[0017] For the purposes of this invention, polyamines are understood to be saturated, open-chain and / or cyclic organic compounds with terminal amino groups and optionally secondary and tertiary amino groups. Such a polyamine can be produced, for example, by reacting ethylenediamine and / or propylenediamine with ethylene oxide, with complete or nearly complete substitution of the oxygen atoms. Furthermore, for example, a reaction of ethylenediamine and / or propylenediamine with epichlorohydrin, with complete or nearly complete substitution of the oxygen and chlorine atoms, is possible. Such polyamines can exist in oligomeric or polymeric form. A cationic surfactant derived from a polyamine is, for example, the salt of a polyamine with an acid, such as acetic acid.

[0018] In a preferred embodiment of the invention, the cationic surfactant has two or more cationic groups. Preferably, the cationic surfactant is a salt of an organic polyamine and / or polyethyleneimine with an acid. The acid can be an organic or inorganic acid, preferably an inorganic acid, for example, hydrochloric acid or sulfuric acid. A surfactant available under the trade name Paragas is further preferred. Paragas is a mixture of various compounds, essentially the salt of a polyethyleneamine / -imine with an acid. With these preferred cationic surfactants, particularly constant MO3 concentrations can be achieved in the propellant cartridge case, i.e., low concentration variations, which results in particularly low tube wear during firing.

[0019] The combustible propellant cartridge according to the invention contains 0.01–2 wt.% cationic surfactant, preferably 0.05–1 wt.%, more preferably 0.07–0.8 wt.%, even more preferably 0.1–0.6 wt.%, and most preferably 0.3–0.5 wt.% cationic surfactant. These concentrations allow for very constant MO₃ concentrations in the propellant cartridge according to the invention, resulting in particularly low tube wear during firing.

[0020] The combustible propellant cartridge according to the invention is characterized in that the concentration of the MoO₃ and / or WO₃ particles in the propellant cartridge is more constant than in prior art propellant cartridges, where the concentration within the cartridge fluctuates considerably and is also subject to strong fluctuations from cartridge to cartridge. A concentration difference around an average value of, for example, 8 wt.% of -3 wt.% within known propellant cartridges, i.e., a minimum value of 5 wt.%, is typical. In contrast, in the propellant cartridge according to the invention, the concentration fluctuations of the MoO₃ and / or WO₃ particles are lower, preferably ≤ 1.5 wt.%, more preferably ≤ 1.0 wt.%, particularly preferably ≤ 0.7 wt.%, and especially ≤ 0.5 wt.%. In the axial direction of the propellant cartridge, the concentration fluctuations are preferably even lower, preferably ≤ 1.0 wt.%, more preferably ≤ 0.5 wt.%.

[0021] The MoO₃ and WO₃ concentrations are measured using a wet chemical method. A piece of the propellant tube is cut out, for example, a punched-out piece measuring 1 cm x 1 cm x the wall thickness of the propellant tube (usually 3.3 mm). This piece is then destroyed by fuming with concentrated nitric acid and subsequent ashing in a muffle furnace at 800 °C. The ash content of the preliminary sample (pulp made from nitrocellulose and cellulose without WO₃) and the loss on ignition of the tungsten trioxide are taken into account. By determining the residual moisture content of the sample, the analytical result can be expressed in relation to the dry matter. w Talk WO 3 = m Auswaage ⋅ 10 6 m Einwaage ⋅ 100 − w H 2 O ⋅ 100 − GV − w Asche m Auswaage = Mass of the inserted pellet after annealing [g] m Inwaage = Mass of the inserted pellet before annealing [g] w(H₂O) = Water content of the inserted pellet [%] GV = Loss on ignition of the talc or tungsten trioxide [%] w(Asche) = Ash content of the preliminary sample, calculated on dry matter [%]

[0022] To determine the total MoO₃ and / or WO₃ concentration, a wet chemical measurement is performed on the entire propellant tube according to the procedure described above. Alternatively, at least three wet chemical measurements of approximately 0.05 to 1.0 cm³ volume each can be performed at randomly selected locations within the propellant tube according to the procedure described above, and the arithmetic mean is calculated. The total MoO₃ and / or WO₃ concentration (ctotal) in the propellant tube is the total mass of MoO₃ and / or WO₃ in the propellant tube, divided by the total mass of the propellant tube.

[0023] The quotient of the average MO 3 concentration in wt.% in a volume element of about 0.05 to 1.0 cm 3< (c VE ) at any point in the propellant tube and the total MO 3 concentration in wt.% (c total ) in the propellant tube is c VE : c total = 0.80 - 1.20, preferably 0.85 - 1.15, most preferably 0.90 - 1.10, with M = Mo and / or W, preferably W.

[0024] The volume element of 0.05 to 1.0 cm³ preferably has a volume of about 0.1 to 0.8 cm³, more preferably about 0.2 to 0.6 cm³, and in particular about 0.33 cm³. It is more preferably a continuous volume element. In a preferred embodiment of the invention, the volume element has the wall thickness of the propellant tube. A propellant tube typically has a length of about 30–90 cm, a diameter of 100–160 mm, and a wall thickness of about 2–4 mm, in particular 3.3 mm.

[0025] Preferably, the volume element for determining c VE has a size of 0.5 cm x 0.5 cm x 0.2 cm to 1.5 cm x 1.5 cm x 0.4 cm, more preferably 0.5 cm x 0.5 cm x 0.33 cm to 1.5 cm x 1.5 cm x 0.33 cm, and most preferably 1.0 cm x 1.0 cm x 0.33 cm. These volume elements, which have the wall thickness of the propellant tube as their thickness, thus represent the deviations in the axial direction of the propellant tube over several measurements. The deviation from the mean value is particularly small in the axial direction. For a volume element for determining c VE with a size of 0.5 cm x 0.5 cm x 0.2 cm to 1.5 cm x 1.5 cm x 0.4 cm, c VE : c total is preferably 0.85 - 1.15, more preferably 0.90 - 1.10, and particularly preferably 0.92 - 1.08. This reflects the concentration variation in the axial direction.

[0026] In a preferred embodiment of the propellant tube according to the invention, the mean particle size d 50 of the MO 3 particles is 0.5 - 2.0 µm, the maximum particle size d 100 of the MO 3 particles is ≤ 20 µm, and the quotient of the average MO 3 concentration in wt.% in a volume element (c VE ) at any location in the propellant tube and the total MO 3 concentration in wt.% (c total ) in the propellant tube c VE : c total = 0.85 - 1.15, preferably 0.90 - 1.10, particularly preferably 0.92 - 1.08, wherein the volume element has a size of 0.5 cm x 0.5 cm x 0.2 cm to 1.5 cm x 1.5 cm x 0.4 cm, wherein the propellant tube has a wall thickness and the 0.2 cm up to 0.4 cm is the wall thickness of the propellant cartridge case.

[0027] The MoO₃ and / or WO₃ concentration can be measured using scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) as an alternative to the wet chemical determination described above. For this purpose, a section of the propellant tube is prepared, and an SEM-EDX measurement is performed on an area of ​​approximately 100 µm x 100 µm. This measurement is taken at the surface and reveals the MoO₃ and / or WO₃ concentration in the upper layer of the section. It is reported as a weight percent. The wet chemical determination, as described above, is preferred.

[0028] In a preferred embodiment of the invention, the MoO₃ and / or WO₃ particles have a relatively uniform particle size, i.e., the particle size distribution is comparatively narrow. This is reflected by a low d₁₀ value compared to the d₅₀ value. According to the invention, the d₅₀ value of the MoO₃ particles (MoO₃ and / or WO₃ particles) is 0.5–2.0 µm, preferably 0.7–1.6 µm, particularly preferably 0.8–1.4 µm, and most preferably 0.9–1.1 µm. The d₁₀ value of the MoO₃ and / or WO₃ particles is ≤ 20 µm, preferably ≤ 15 µm, further preferably ≤ 12 µm, and particularly preferably ≤ 10 µm. These particle sizes make it possible to achieve very constant MO 3 particle concentrations in the propellant charge sleeve according to the invention, i.e.particularly low concentration variations, which results in low pipe wear during injection, and furthermore these uniform particle sizes have the advantage that they themselves ensure low temperature and pressure peaks during injection, which can further reduce pipe wear.

[0029] A uniform particle size, in the sense of a narrow particle size distribution, is achieved by mixing the slurry in the process according to the invention in the presence of a cationic surfactant, preferably for at least 15 minutes. Mixing is preferably carried out by stirring. While not strictly required by the invention, it is assumed that the cationic surfactant coats the regularly slightly negatively charged MoO₃ and / or WO₃ particles (MoO₃ and WO₃ are slightly acidic in aqueous media), thereby keeping the MoO₃ and / or WO₃ particles in suspension and thus promoting recrystallization, i.e., dissolution and recrystallization.Even when a broad particle size distribution of the MoO3 and / or WO3 particles used is employed, after carrying out the method according to the invention, the particle size distribution in the propellant cartridge case is very narrow, for example, d50 = 0.5 to 2.0 µm, preferably 0.8 to 1.4 µm, with d100 ≤ 15 µm, preferably ≤ 12 µm, particularly preferably ≤ 10 µm. This narrowing of the particle size distribution results in a more uniform thermal and pressure load in the weapon barrel, thereby avoiding thermal and pressure peaks and reducing barrel wear.

[0030] According to the invention, the average concentration of MO 3 in the propellant tube (total MO 3 concentration) is 5–10 wt.%, preferably 6–9 wt.%, and particularly preferably 7–8 wt.%, where M = Mo and / or W. M is preferably tungsten (W). In a preferred embodiment of the invention, the propellant tube contains, in addition to the MoO 3 and / or WO 3 particles, less than 1 wt.%, preferably less than 0.5 wt.%, and particularly preferably less than 0.1 wt.% other metal oxide particles.

[0031] The combustible propellant tube according to the invention preferably contains 45 - 65 wt.%, in particular 52 - 58 wt.%, nitrocellulose and / or 25 - 50 wt.%, in particular 33 - 40 wt.%, cellulose.

[0032] The method according to the invention comprises the steps (a) Preparing a slurry of cellulose, nitrocellulose, MO 3 particles, where M = Mo and / or W, and cationic surfactant in water, (b) mixing the slurry, preferably for at least 5 minutes, more preferably for at least 20 minutes, particularly preferably for 30 minutes to 2 hours, (c) dewatering the slurry on a screen to produce a raw felt, (d) pressing the raw felt, and (e) drying it to form a combustible propellant tube.

[0033] In a preferred embodiment of the invention, the slurry in step (a) contains 5 - 10 wt.% MO 3 particles, based on the total weight of pulp, nitrocellulose, MO 3 particles and cationic surfactant and / or 0.1 - 2 wt.% cationic surfactant, based on the total weight of pulp, nitrocellulose, MO 3 particles and cationic surfactant.

[0034] The inventive method preferably comprises the steps (a) Preparing a slurry (pulp) of cellulose, nitrocellulose, 5-10 wt% MO3 particles, based on the total weight of the propellant tube, where M = Mo and / or W, and 0.1-2 wt% cationic surfactant, based on the total weight of the propellant tube, in water; (b) mixing the slurry, preferably for at least 5 minutes, more preferably for at least 20 minutes, particularly preferably for 30 minutes to 2 hours; (c) dewatering the slurry on a screen to produce a raw felt; (d) pressing the raw felt; and (e) drying to form a combustible propellant tube.

[0035] The surfactant preferably partially adheres to fibers, so that the amount of surfactant in the sleeve is preferably somewhat less than in the slurry used.

[0036] In a preferred embodiment of the method according to the invention, in step (a) A slurry in water is prepared from 45–65 wt% nitrocellulose, 25–50 wt% cellulose, 5–10 wt% MoO₃ and / or WO₃ particles, and 0.1–2 wt% cationic surfactant, the wt% each based on the total mass of nitrocellulose, cellulose, MoO₃ and / or WO₃ particles and / or cationic surfactant, and optionally additives, stabilizers, and / or binder resin. It is understood that the sum of the wt% of the individual components equals 100 wt%. A preferred stabilizer is acardite.

[0037] The pressing of the raw felt in step (d) preferably takes place at 20 - 175 °C, more preferably at 100 - 175 °C, most preferably at 120 - 150 °C.

[0038] Drying preferably takes place under ambient conditions, especially in a so-called standard climate.

[0039] In a preferred embodiment of the process according to the invention, a stabilizer is additionally added in step (a). The stabilizer is preferably acardite (diphenylamine). This stabilizer serves in particular to stabilize the nitrocellulose.

[0040] In a further preferred embodiment of the process according to the invention, a binding resin is additionally added in step (a). The binding resin can, for example, be added in the form of binding resin particles. During subsequent pressing at elevated temperature, the binding resin melts and bonds the fibers together. The binding resin is preferably a polymer or a polymer mixture of polystyrene-polybutadiene rubber (latex).

[0041] In a preferred embodiment of the invention, a lacquer is applied to the surface of the propellant cartridge case after step (e). A nitrocellulose lacquer is preferred. It is preferred that, when using a lacquer, the binder resin described above is added in step (a).

[0042] In a further preferred embodiment of the method according to the invention, a plastic is applied to the surface of the compressed raw felt between steps (d) and (e). The plastic is preferably a polyurethane (PU). This is preferably done by immersing the compressed raw felt in a bath of polyols with an isocyanate crosslinker and subsequent drying, whereby the polyurethane hardens.

[0043] Preferably, the method according to the invention comprises the steps (a) Producing a slurry (pulp) of cellulose, nitrocellulose, MO 3 particles, wherein M = Mo and / or W, and cationic surfactant in water, (b) Mixing the slurry, preferably for at least 15 minutes, (c) Dewatering the slurry on a screen to produce a raw felt, (d1) Pressing the raw felt, (d2) Applying a plastic to the surface of the pressed raw felt, preferably a polyurethane, and (e) Drying to form a combustible propellant tube.

[0044] The inventive method preferably also comprises the steps (a) Preparation of a slurry (pulp) of cellulose, nitrocellulose and binder resin particles in water, addition of MO 3 particles, wherein M = Mo and / or W, and cationic surfactant in water, (b) mixing of the slurry, preferably for at least 15 minutes, (c) dewatering of the slurry on a sieve mold to produce a raw felt, (d) pressing of the raw felt and (e) drying to form a combustible propellant tube, (f) application of a lacquer to the surface of the combustible propellant tube, preferably a nitrocellulose lacquer.

[0045] The slurry (pulp) is preferably mixed using conventional stirring tools, for example, rotating blades. The slurry is dewatered by pouring it onto a sieve mold, allowing the water to drain through the sieve holes, optionally assisted by a vacuum. The raw felt is then pressed onto this sieve mold with a matching counterpart, producing a still slightly moist propellant tube, which is subsequently dried to manufacture the combustible propellant tube according to the invention.

[0046] The present invention also relates to the use of the propellant cartridge case according to the invention for firing ammunition, in particular artillery ammunition.

[0047] The invention is further explained below using two examples: Example 1:

[0048] Production of combustible casings for tank gun ammunition 1. Pulp sheets are beaten into a pulp in water (2627 liters of process water). This is done in a container with a rotating blade at the bottom. Initial weight: 78.8 kg. The pulp is then ground in a refiner. Another 1200 liters of process water are added. 2. Nitrocellulose is stirred into the pulp. Initial weight: 120.0 kg. 3. Density check: approx. 8%. 4. Another 1600 liters of process water are added. 5. Paragas is added: The paragas is mixed with water and added to the mixture while stirring. 6. The stabilizer acardite is added: The acardite is suspended in water and ground. It is then added to the mixture while stirring. 7. 16.8 kg of WO3 particles are suspended in 32 liters of water and added to the mixture while stirring. 8. The mixture is pumped into the target container and diluted with process water. 9.The fibers are separated onto screens by suction in special basins that are in contact with the receiving container. This produces the raw felt. 10. The raw felts are then pressed at approximately 170 °C. During pressing, the water is removed from the raw felt by vacuum. This step produces the sleeve in its defined shape. 11. The pressed sleeves are PU-impregnated by briefly immersing them in a bath of polyols with an isocyanate crosslinker, followed by drying and curing in a drying tunnel. 12. Conditioning under standard climate conditions (drying). 13. Mechanical cutting to length and chamfering. Example 2: Manufacturing combustible casings for artillery ammunition

[0049] Steps 1-3 are identical.

[0050] Step 4 involves adding binding resin particles. These particles are later melted during pressing and bond the fibers together. They are polymers made of polystyrene-polybutadiene latex.

[0051] Raw felt production and pressing analogous to the process described above.

[0052] Step 11 is omitted here.

[0053] Steps 12 and 13 are carried out analogously.

[0054] Finally, a painting step follows. The painting is done with an NC lacquer containing the appropriate color pigment.

[0055] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the present invention. The advantages of features or combinations of several features mentioned are merely examples and can have an effect alternatively or cumulatively. The combination of features from different embodiments of the invention or features from different claims is possible, deviating from the chosen cross-references in the claims.

Claims

1. Combustible propellant charge sleeve for ammunition that can be fired from an armor barrel, comprising - pulp, - nitrocellulose, - 5 - 10 % by weight of MO3 particles, based on the total weight of the propellant charge sleeve, wherein M = Mo and / or W, and - 0.01 - 2 % by weight of cationic surfactant, based on the total weight of the propellant charge sleeve, wherein the average particle size d50 of the MO3 particles is 0.5 - 2.0 µm, the maximum particle size d100 of the MO3 particles is ≤ 20 µm, and the quotient of the average MO3 concentration in % by weight in a volume element of about 0.05 to 1.0 cm3 (cVE) at any point in the propellant charge sleeve and the total MO3 concentration in % by weight (ctotal) in the propellant charge sleeve is cVE : ctotal = 0.80 - 1.20.

2. Combustible propellant charge sleeve according to claim 1, characterized in that the average particle size d50 of the MO3 particles is 0.8 - 1.4 µm.

3. Combustible propellant charge sleeve according to claim 1 or 2, characterized in that the d100 value of the MO3 particles is ≤ 12 µm.

4. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that the propellant charge sleeve contains 7 - 8% by weight of MO3 particles and / or 0.05 - 1% by weight of cationic surfactant.

5. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that cVE : ctotal = 0.85 - 1.15.

6. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that the volume element has a size of about 0.5 cm x 0.5 cm x 0.2 cm to 1.5 cm x 1.5 cm x 0.4 cm, wherein the propellant charge sleeve has a wall thickness, the 0.2 cm to 0.4 cm being the wall thickness of the propellant charge sleeve, and it is cVE : ctotal = 0.90 - 1.10.

7. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that the quotient of the average MO3 concentration in % by weight in a volume element of about 0.33 cm3 (cVE) at any point in the propellant charge sleeve and the total MO3 concentration in % by weight (ctotal) in the propellant charge sleeve is cVE : ctotal = 0.80 - 1.

208. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that M = W.

9. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that the cationic surfactant contains two or more cationic groups.

10. Combustible propellant charge sleeve according to any of the preceding claims, characterized in that the cationic surfactant is a salt of an organic polyamine and / or polyethyleneimine with an acid.

11. Process of manufacturing a combustible propellant charge sleeve according to any one of claims 1 - 10, comprising the steps of (a) preparing a slurry of pulp, nitrocellulose, MO3 particles, wherein M = Mo and / or W, and cationic surfactant in water, (b) mixing the slurry, (c) dewatering the slurry on a sieve mold to prepare a raw felt, (d) pressing the raw felt and (e) drying to form a combustible propellant charge sleeve.

12. Process according to claim 11, characterized in that the slurry in step (a) contains 5 - 10 % by weight of MO3 particles, based on the total weight of pulp, nitrocellulose, MO3 particles and cationic surfactant, and / or 0.1 - 2 % by weight of cationic surfactant, based on the total weight of pulp, nitrocellulose, MO3 particles and cationic surfactant.

13. Process according to claim 11 or 12, characterized in that the cationic surfactant contains two or more cationic groups, preferably the cationic surfactant is a salt of an organic polyamine with an acid.

14. Process according to any one of claims 11 to 13, characterized in that a stabilizer is additionally added in step a), preferably acardite.

15. Use of a combustible propellant charge sleeve according to any of claims 1 to 10 for firing ammunition, in particular artillery ammunition.