EP1364931B1 - Gun propellant powders of high power and reduced erosive action - Google Patents

Description

The present invention is in the general field of tube weapons, and more particularly relates to new propellant powders intended to ensure the propulsion of a projectile with this type of weapons.

Tube weapons, which are well known to those skilled in the art, make it possible to launch a projectile, generally a bullet or a shell, in a determined direction, with a determined force obtained by the rapid production of a large quantity of gas resulting from the combustion of a propellant powder.

Examples of such weapons include handguns such as pistols and revolvers, long guns such as rifles and rifles, and guns such as machine guns and cannons.

The problem of the wear and the physical and / or chemical erosion of the internal wall of the tube of these weapons during the shots caused by the friction of the projectile, the hot gases of combustion of the propellant powder and possibly solid particles emitted by the burning powder, is well known for a long time, especially when using dual-base propellant powders such as those based on a nitrocellulose binder plasticized with nitroglycerin, which are certainly more energetic than powders single base essentially consisting of nitrocellulose, but which are very clearly more erosive.

It is also well known that the predominant factor of the erosivity of a powder is the combustion temperature. The higher this temperature, the more erosive the powder, whatever the composition of the powder. The determination of the combustion temperature makes it easy to compare the erosivity of various powders.

J. QUINCHON et al., In the work "powders, propellants and explosives", Volume 3: powders for weapons, Technique and Documentation (Lavoisier), 1986, pages 18 to 20 , mention the use of nitroguanidine to reduce the erosivity of double-base powders for weapons, but the effectiveness of this compound is limited, which requires the formulation of compositions containing 30% to 55% by weight, and there is then an undesirable decrease in the strength of the powder, which corresponds to the pressure developed by the combustion of 1 kg of powder in a constant volume of 1 m ³ and which is a specific energy of the powder, and thus the initial velocity of the projectile and the performance of the weapon.

The patent DE 201-215 discloses a powder for tube weapons comprising nitrocellulose, nitroglycerine and 4% by weight of melamine. The patent US 4,098,193 proposes, in order to reduce the erosion of the weapon tube wall, to incorporate, in a munition containing a double-base propellant powder, an anti-erosive sleeve between the envelope and the propellant powder. This anti-erosion sleeve consists of a fabric support impregnated with a decomposable organic compound rich in nitrogen such as a tetrazole, a polyvinyl tetrazole or an organic azide.

The manufacture of such a sleeve is however long, expensive and complex. The sleeve, once obtained, must then be positioned in the cartridge, which constitutes a further penalizing step. In addition, the performance of the weapon is decreased for a given cartridge, since the sleeve has a force significantly lower than that of the powder and occupies a certain volume at the expense of the same volume of powder.

In the state of the art, therefore, there is no really satisfactory solution to the problem, which has been known for a very long time, of the erosivity of propellant powders for weapons, especially double-base powders.

The present invention provides a solution to this problem.

It has been discovered that, unexpectedly, the erosivity and the strength of the nitrocellulose-nitroglycerine double-base powders can be simultaneously reduced by incorporating into the composition of these powders certain very particular nitrogenous organic energy compounds.

This double technical effect, ie decrease in erosivity and increase in strength, was only observed with nitrocellulose-nitroglycerin double-base powders. The following comparative examples show that, in a particularly unexpected manner, this double technical effect does not exist when these same nitrogenous organic energy compounds are incorporated in a single propulsive powder or in a double-base propellant powder in which the nitroglycerine is replaced by another nitrated oil such as diethylene glycol dinitrate (NEO) and triethylene glycol dinitrate (TRENO), or alternatively in a composite powder based on a nitramine feed coated with a non-nitrated polymer, for example polyurethane.

This way of operating, according to the present invention, is, moreover, particularly simple and inexpensive, since it is sufficient to introduce an additional ingredient in the mixer during the mixing of the constituents, according to a method quite analogous to that used in the state of the art to obtain nitrocellulose / nitroglycerin / nitroguanidine powders.

• une teneur pondérale globale nitrocellulose + nitroglycérine comprise entre 50 % et 95 % par rapport au poids total de la composition ;
• un rapport pondéral nitrocellulose/nitroglycérine compris entre 2,5 et 1 ; et
• une teneur pondérale dudit composé organique énergétique azoté comprise entre 5 % et 50 % par rapport au poids total de la composition ; ledit composé organique énergétique azoté ayant une enthalpie de formation supérieure à 418,7 J/g (+ 100 cal/g).

The novel propellant powders for tube weapons according to the invention have a composition based on nitrocellulose and nitroglycerine, which comprises another nitrogenous organic energetic compound consisting solely of carbon, nitrogen and hydrogen and comprising at least a nitrogen heterocycle. The composition of these new powders present:

• an overall nitrocellulose + nitroglycerine weight content of between 50% and 95% relative to the total weight of the composition;
• a nitrocellulose / nitroglycerin weight ratio of between 2.5 and 1; and
• a weight content of said organic nitrogenous energy compound of between 5% and 50% relative to the total weight of the composition; said nitrogenous energetic organic compound having an enthalpy of formation greater than 418.7 J / g (+100 cal / g).

The enthalpy of formation of this nitrogenous organic energetic compound is greater than 418.7 J / g (+ 100cal / g). Preferably, it is better still greater than 674.7 J / g (+400cal / g), better still greater than 2512.1 J / g (+600cal / g) and even more preferably greater than 3768.1 J / g (+ 900cal / g).

This nitrogenous energetic organic compound, which, at ambient temperature, can be in the solid state as well as in the liquid state at about 20 ° C., is preferably chosen from the group consisting of diaziridines and triazoles. , triazines, tetrazoles and tetrazines.

Examples of such compounds include diaminotriazine, dimethylbistetrazole, trihydrazinotriazine, 5-amino-tetrazole, aminotetrazolotetrazine, 3,3'-azobis (6-amino-s-tetrazine) and 3,6-azabis. dihydrazino-s-tetrazine.

It is also possible to use, without this list being exhaustive, a pyrrole, aziridine or tetrazoline.

It is also possible, of course, to use any mixture of at least two of the abovementioned compounds.

The weight content of the nitrogenous organic energetic compound is between 5% and 50% relative to the total weight of the composition. It is preferably between 10% and 30%. On the one hand, it can be seen that the combustion temperature of the powder, and therefore its erosivity, decreases as the weight content of the nitrogenous organic energetic compound increases, and on the other hand that the strength of the powder increases, reaches a maximum, and then generally decreases, when the weight content of nitrogenous organic energetic compound is increased.

This unexpected behavior makes it possible to orient the choice of compositions between those having a maximum force, much higher than that of the reference powder, with a lower erosivity, and those having a force close to that of the reference powder with erosivity. greatly reduced.

The overall weight content of nitrocellulose and nitroglycerine is between 50% and 95% relative to the total weight of the composition.

The nitrocellulose / nitroglycerin weight ratio is between 2.5 and 1.

According to the invention, any nitrocellulose usually used in double-base powders can be used.

The propellent powders according to the invention can also comprise in their composition the additives usually present in the double-base powders, for example a stabilizer such as the centralite, graphite to make the conductive powders of static electricity and to facilitate the charging and / or or an anti-glare agent such as a potassium salt.

According to another preferred variant of the invention, the compositions of the propellant powders according to the invention also comprise a nitramine pulverulent filler, preferably hexogen, octogen or hexanitrohexaazaisowurtzitane. In this case, the weight content of nitramine pulverulent filler is preferably between 5% and 40% relative to the total weight of the composition.

The novel powders for tube weapons according to the invention can be obtained by methods analogous to those used in the state of the art to obtain double-base nitrocellulose / nitroglycerine powders or nitrocellulose / nitroglycerin / nitroguanidine triple base powders, optionally "doped" with a nitramine charge.

A first method well known to those skilled in the art is a solvent-free process. According to this method, a slab is first prepared from an aqueous suspension of nitrocellulose in which an aqueous emulsion of nitroglycerine is added, suspension which is filtered after homogenization with the dough press.

This cake is moistened for safety reasons for storage and transport.

The wetted slab (35 to 40% water in general) is first dewatered to reduce the water content to around 20%, then subjected to a mixing of moisture in a paddle mixer to better homogenize the water in the product.

The other constituents are then added to the kneader and then kneaded so as to obtain a homogeneous product which then undergoes a double mechanical and thermal action in a rolling mill which will make it possible to expel the water and the nitroglycerin to penetrate the nitrocellulose fiber. .

The powder is then shaped by press extrusion and cutting or by calendering and cutting according to the desired shape and dimensions.

When this method is used without solvent to obtain the powders according to the invention, the organic nitrogen-containing compound consisting solely of carbon, nitrogen and hydrogen and comprising a nitrogenous heterocycle is added to the paddle mixer as other constituents than nitrocellulose and nitroglycerine.

A second method well known to those skilled in the art is a semi-solvent process. According to this method, the mixture is first mixed in a kneader nitrocellulose dehydrated with alcohol with nitroglycerin dissolved in acetone as well as with the other constituents of the powder.

The powder is then shaped according to the same operations as those mentioned above for the solvent-free process, and then the solvents are removed by steaming.

When this semi-solvent process is used to obtain the powders according to the invention, the nitrogenous organic energetic compound is added to the kneader as other constituents of the powder.

The present invention also relates to a method for lowering the erosive effect and increasing the strength of a propellant powder for nitrocellulose and nitroglycerin-based tube weapons.

According to this process, this powder, the composition of which has a nitrocellulose / nitroglycerin weight ratio of between 2.5 and 1, is incorporated into an organic energy compound composed solely of carbon, nitrogen and hydrogen and comprising at least one nitrogen heterocycle, said nitrogenous energetic organic compound having an enthalpy of formation greater than 418.7 J / g (+100 cal / g); said compound being incorporated in a weight content such that the composition of the powder incorporating it contains between 5% and 50% of said compound and between 50% and 95% of nitrocellulose + nitroglycerin, relative to the total weight of said composition.

The following nonlimiting examples illustrate the invention and the advantages it provides.

For all these examples, the powder samples were obtained according to the semi-solvent method mentioned above. The constituents are introduced into a horizontal kneader, firstly nitrocellulose (13.15% nitrogen) in the form of 25% ethanol and then the nitroglycerine phlegmatized with 30% acetone. The other constituents are then progressively added.

The level of acetone and ethanol is adjusted to obtain a good homogenization of the dough. The watering rate varies according to the compositions.

The mixing time is about 3 hours.

The dough is then spun in a press pot. The geometry of the die is a 7-hole die with an outside diameter of 2.7 mm, a perforation diameter of 0.3 mm and a web of 0.45 mm.

The spun strands are left at room temperature (about 20 ° C.) to allow a slight evaporation of the solvents and to obtain a consistency that is favorable to cutting.

The strands are then cut with a guillotine cutter to a length such that the length / diameter ratio is equal to 1.1.

The powder grains are then dried in an oven for several days at a temperature between 40 ° C and 70 ° C.

The combustion temperatures of the powders were determined by calculation, according to a method well known to those skilled in the art.

The strength of the powders was determined, according to the examples, either by calculation or from experimental measurements of gunshots by methods also well known to those skilled in the art.

When the force has been determined by calculation, the value mentioned in the following tables is followed by the indication (c).

When the force has been determined from experimental measurements, the value mentioned is followed by the indicator (m).

The actual tests of erosivity were carried out in an erosion-grain bomb, the flue gases being evacuated by a nozzle whose mass loss is measured.

Examples 1 to 23 - Propellant powders consisting of nitrocellulose / nitroglycerin 60/40 by weight and a nitrogen-containing organic compound consisting solely of C, H, N and comprising at least one nitrogenous heterocycle, at various contents by weight

According to the compositions, if x is denoted by the weight content in the compositions of nitrogen-containing organic compounds consisting solely of C, H, N and comprising at least one nitrogenous heterocycle, the weight content of nitrocellulose is 0.6 (100-x ) and 0.4 nitroglycerin (100-x).

According to Examples 1 to 4, the nitrogenous organic compound is dimethylbistetrazole (DMBT), of empirical formula C ₄ H ₆ N ₈ , whose formation heat is 3140.1 J / g (+750 cal / g).

According to Examples 5 to 8, the nitrogenous organic compound is 5-aminotetrazole (5AT), of empirical formula CH ₃ N ₅ , whose formation heat is 2445.1 J / g (+ 584 cal / g).

According to Examples 9 to 13, the nitrogenous organic compound is 3,6-dihydrazino-s-tetrazine (DHT), of empirical formula C ₂ H ₆ N ₈ , whose formation heat is 3772.3 J / g (+ 901 cal / g).

According to Examples 14 to 17, the nitrogenous organic compound is the diaziridine of formula C ₁₀ H ₁₄ N ₄ , whose formation heat is 4551.1 J / g (+1087 cal / g) of structural formula:

According to Examples 18 and 19, the nitrogenous organic compound is 3,3'-azobis (6-amino-s-tetrazine) (DATT), of empirical formula C ₄ H ₄ N ₁₂ , whose formation heat is 3923 J. g (+937 calg / g).

According to Examples 20 to 23, the nitrogenous organic compound is aminotetrazolotetcazine (AAT), of empirical formula C ₂ H ₂ N ₈ , whose formation heat is 5401 J / g (+1290 cal / g).

The following Table 1 specifies, for these examples 1 to 23, the strength and the combustion temperature of the powders, compared on the one hand with the base powder (x = 0) whose erosive effect is to be lowered (comparative example A ), and on the other hand to known powders of the state of the technique with nitroguanidine (NGU) as an antérosive additive, of empirical formula CH ₄ N ₄ O ₂ , whose formation heat is 908.5 J / g (-217 cal / g) (Comparative Examples B, C, D and E).

It can be seen that, contrary to Examples 1 to 23 according to the invention, the NGU does not make it possible to increase the strength of the powders, that for NGU contents of less than about 20%, the erosivity decrease is very minimal with maintenance. strength and that the decrease in erosivity is more consistent for NGU contents between 30% and 50%, but the force is then significantly reduced.

For Examples 4 and 8, real erosivity tests were performed as well as for the base powder (Comparative Example A).

Compared to the erosivity observed with the base powder, there is a decrease in erosivity of 50% for Example 4 and 40% for Example 8. Table 1 Example N ° DMBT (%) SAT (%) DHT (%) DiAl (%) DAAT (%) AAT (%) NGU (%) Strength (MJ / kg) Combustion temperature (K) Comparative A - - - - - - - 1.17 (m) (c) 3,884 1 4.8 - - - - - - 1.19 (m) 3,794 2 9.1 - - - - - - 1.20 (m) 3,685 3 16.7 - - - - - - 1.19 (m) 3,453 4 23.1 - - - - - - 1.18 (m) 3,233 5 - 4.8 - - - - - 1.18 (m) 3,809 6 - 9.1 - - - - - 1.19 (m) 3,727 7 - 16.7 - - - - - 1.19 (m) 3,553 8 - 23.1 - - - - - 1.18 (m) 3387, 9 - - 9.1 - - - - 1.22 (c) 3,763 10 - - 20.0 - - - - 1.24 (c) 3,556 11 - - 28.6 - - - - 1.25 (c) 3,371 12 - - 35.5 - - - - 1.25 (c) 3,216 13 - - 41.2 - - - - 1.25 (c) 3,087 14 - - - 4.8 - - - 1.22 (c) 3,710 15 - - - 9.1 - - - 1.23 (c) 3,483 16 - - - 16.7 - - - 1.21 (a) 3,047 17 - - - 23.1 - - - 1.17 (c) 2,700 18 - - - - 9.1 - - 1.20 (c) 3,791 19 - - - - 25.9 - - 1.21 (c) 3,510 20 - - - - - 13.0 - 1.23 (c) 3,859 21 - - - - - 23.1 - 1.27 (c) 3,818 22 - - - - - 35.5 - 1.31 (c) 3,746 23 - - - - - 50.0 - 1.36 (c) 3,640 Comparative B - - - - - - 9.1 1.17 (m) 3,781 Comparative C - - - - - - 16.7 1.17 (m) 3,685 Comparative D - - - - - - 30.0 1.15 (m) 3,492 Comparative E - - - - - - 50.0 1.11 (m) 3,170

Examples 24 to 39 - Propellant powders consisting of 60% by weight of nitrocellulose, nitroglycerine and a nitrogen-containing organic compound consisting solely of C, H, N and comprising at least one nitrogenous heterocycle, at various contents by weight

According to the compositions, which all comprise 60% by weight of nitrocellulose, if x is denoted by the weight content in the organic nitrogen compound compositions consisting solely of C, H, N and comprising at least one nitrogenous heterocycle, the weight content nitroglycerin is (40-x).

According to Examples 24 to 26, the nitrogenous organic compound is the diaziridine of formula C ₅ H ₈ N ₂ , whose formation heat is 4530.1 J / g (+1082 cal / g), of structural formula:

According to Examples 27 to 29, the nitrogenous organic compound is diaziridine of the empirical formula C ₈ H ₁₀ N ₂ , the formation heat of which is 4940.4 J / g (+1180 cal / g), of structural formula:

According to Examples 30 to 32, the nitrogenous organic compound is diaziridine of the empirical formula C ₇ H ₈ N ₂ , whose formation heat is 5752.7 J / g (+1374 cal / g), of structural formula:

According to Examples 33 and 34, the nitrogenous organic compound is diaziridine of the empirical formula C ₆ H ₁₂ N ₂ , whose formation heat is 2164.6 J / g (+517 cal / g), of structural formula:

According to Examples 35 to 39, the nitrogenous organic compound is the diaziridine of formula C ₅ H ₁₀ N ₈ , the formation heat of which is 4442.2 J / g + 1061 cal / g, of structural formula:

The following table 2 specifies, for these examples 24 to 39, the strength and the combustion temperature of the powders, compared with the base powder (x = 0) whose erosive effect is to be lowered (comparative example A). <u> Table 2 </ u> Example N ° DiA2 (%) DiA3 (%) DiA4 (%) DiA5 (%) DiA6 (%) Strength (MJ / kg) Combustion temperature (K) Comparative A - - - - - 1.17 (m) (c) 3,884 24 5 - - - - 1.21 (c) 3,645 25 10 - - - - 1.21 (c) 3,312 26 15 - - - - 1.18 (c) 2,962 27 - 5 - - - 1.21 (c) 3,638 28 - 10 - - - 1.21 (c) 3,290 29 - 15 - - - 1.17 (c) 2,924 30 - - 5 - - 1.21 (c) 3,638 31 - - 10 - - 1.21 (c) 3,290 32 - - 15 - - 1.17 (c) 2,924 33 - - - 5 - 1.20 (c) 3,547 34 - - - 10 - 1.17 (c) 3,104 35 - - - - 5 1.21 (c) 3,755 36 - - - - 10 1.22 (c) 3,573 37 - - - - 15 1.22 (c) 3,365 38 - - - - 20 1.21 (c) 3,149 39 - - - - 25 1.19 (c) 2,931

Examples 40 to 44 - Propellant powders consisting of 25% by weight of hexogen, nitrocellulose and nitroglycerin in a weight ratio of 60/40, and a nitrogen-containing organic compound consisting solely of C, H, N and comprising at least one nitrogen heterocycle, at various levels

According to the compositions, if we denote by x the weight content in the composition of nitrogen-containing organic compound consisting solely of C, H, N and comprising at least one nitrogenous heterocycle, the weight content of nitrocellulose is 0.6 (75 - x ) and 0.4 nitroglycerin (75 - x).

According to Examples 40 and 41, the nitrogenous organic compound is dimethylbistetrazole (DMBT) already used for Examples 1 to 4.

According to Examples 42 to 44, the nitrogenous organic compound is 3,6-dihydrazino-s-tetrazine (DHT) already used for Examples 9 to 13.

The following Table 3 specifies, for these examples 40 to 44, the strength and the temperature of combustion of the powders, compared with the base powder (x = 0) whose erosion effect is to be reduced and which consists of 45% by weight. nitrocellulose weight, 30% by weight of nitroglycerine and 25% by weight of hexogen (Comparative Example F).

For Example 41, a real erosivity test was performed, as well as for the base powder (Comparative Example F).

Compared with the erosivity observed with the base composition, there is a decrease in erosivity of 45% for Example 41. <u> Table 3 </ u> Example N ° DMBT (%) DHT (%) Strength (MJ / kg) Combustion temperature (K) Comparative F - - 1.22 (m) (c) 3,932 40 10 - 1.25 (m) 3,706 41 20 - 1.24 (m) 3,388 42 - 10 1.27 (c) 3,794 43 - 20 1.30 (c) 3,603 44 - 30 1.31 (c) 3,388

Comparative Examples G to O, P1 to P9 and Q1 to Q7

As for Comparative Examples A to F above, these Comparative Examples G to O, P ₁ to P ₉ and Q ₁ to Q ₇ do not form part of the invention. They were carried out in order to show that the double technical effect observed according to the invention, namely a decrease in erosivity and an increase in the strength, only surprisingly occurs with nitrocellulose / nitroglycerin double-base powders. and is not found for the other types of powders, in particular for the nitrocellulosic single base powders, for the double-base powders in which the nitroglycerine is replaced by another nitrated oil, as well as for the composite powders with inert binder.

According to comparative examples G to O, nitrocellulose / triethylene glycol dinitrate (TRENO) double base propellant powders were prepared in the respective weight proportions 60/40.

According to Comparative Example G, the powder contains only these 2 constituents.

According to Comparative Examples H, I, J and K, the powder also contains DMBT at various weight contents, as for Examples 1 to 4 according to the invention.

According to Comparative Examples L, M, N and O, the powder also contains 5AT, as for Examples 5 to 8 according to the invention.

According to these comparative examples H to O, if x is the weight content in the DMBT or 5AT compositions, the weight content of nitrocellulose is 0.6 (100-x) and that in TRENO 0.4 (100- x).

The following Table 4 specifies, for these Comparative Examples G to O, the strength and the combustion temperature of the powders. <u> Table 4 </ u> Comparative Example DMBT (%) 5AT (%) Strength (MJ / kg) Combustion temperature (K) BOY WUT - - 1.06 (m) 2,764 H 4.8 - 1.04 (m) 2,660 I 9.1 - 1.02 (m) 2,566 J 13.0 - 1.01 (m) 2,482 K 16.7 - 0.99 (m) 2,410 The - 4.8 1.04 (m) 2,692 M - 9.1 1.03 (m) 2,626 NOT - 13.0 1.02 (m) 2,567 O - 16.7 1.01 (m) 2,513

According to Comparative Examples P ₁ to P ₉ , nitrocellulose single propellant powders consisting of nitrocellulose and DMBT were prepared for Comparative Examples P ₂ to P ₅ , nitrocellulose and 5AT for Comparative Examples P ₆ to P ₉ .

For comparative example P ₁ , the powder contains only nitrocellulose.

The following table 5 specifies, for these comparative examples P ₁ to P ₉ , the force and the combustion temperature of the powders. <u> Table 5 </ u> Comparative Example DMBT (%) 5AT (%) Strength (MJ / kg) Combustion temperature (K) P ₁ - - 1.10 (m) 3,324 P ₂ 5 - 1.09 (m) 3,185 P ₃ 10 - 1.07 (m) 3,041 P ₄ 20 - 1.04 (m) 2,750 P ₅ 30 - 0.99 (m) 2,475 P ₆ - 5 1.09 (m) 3,220 P ₇ - 10 1.08 (m) 3,113 P ₈ - 20 1.05 (m) 2,895 P ₉ - 30 1.02 (m) 2,678

According to Comparative Examples Q1 to Q7, composite propellant powders were made based on a hexogen loaded polyester polyurethane inert rubber matrix.

For comparative example Q ₁ , the powder consists of 10% by weight of inert matrix and 90% by weight of hexogen.

For comparative examples Q ₂ to Q ₇ , the powder consists of 10% by weight of inert matrix, x% by weight of DMBT or 5AT and (90-x)% by weight of hexogen.

The following table 6 specifies, for these comparative examples Q1 to Q7, the strength and the combustion temperature of the powders. <u> Table 6 </ u> Comparative Example DMBT (%) 5AT (%) Strength (MJ / kg) Combustion temperature (K) Q ₁ - - 1.31 (m) 3,440 Q ₂ 5 - 1.28 (m) 3,265 Q ₃ 10 - 1.25 (m) 3,086 Q ₄ 20 - 1.17 (m) 2,735 Q ₅ - 5 1.28 (m) 3,298 Q ₆ - 10 1.25 (m) 3,153 Q ₇ - 20 1.19 (m) 2,859

Claims (10)

1. A propellant powder for tube weapons, the composition of which is based on nitrocellulose and nitroglycerine and comprises another energetic nitrogenous organic compound composed solely of carbon, nitrogen and hydrogen and comprising at least one nitrogenous heterocycle, characterized in that said composition has:

   - a nitrocellulose + nitroglycerine overall weight content between 50% and 95% with respect to the total weight of the composition;

   - a nitrocellulose/nitroglycerine weight ratio between 2.5 and 1; and

   - a weight content of said energetic nitrogenous organic compound between 5% and 50% with respect to the total weight of the composition; said energetic nitrogenous organic compound having an enthalpy of formation greater than 418.7 J/g (+ 100 cal/g).
2. The propellant powder according to claim 1, characterized in that said composition has a weight content of said energetic nitrogenous organic compound between 10% and 30% with respect to the total weight of the composition.
3. The propellant powder according to claim 1 or 2, characterized in that said energetic nitrogenous organic compound has an enthalpy of formation greater than 1674.7 J/g (400 cal/g).
4. The propellant powder according to claim 1 or 2, characterized in that said energetic nitrogenous organic compound has an enthalpy of formation greater than 2512.1 J/g (600 cal/g).
5. The propellant powder according to claim 1 or 2, characterized in that said energetic nitrogenous organic compound has an enthalpy of formation greater than 3768.1 J/g (900 cal/g).
6. The propellant powder according to any one of claims 1 to 5, characterized in that said energetic nitrogenous organic compound is selected from the group consisting in the diaziridines, the triazoles, the triazines, the tetrazoles and the tetrazines.
7. The propellant powder according to any one of claims 1 to 5, characterized in that said energetic nitrogenous organic compound is selected from the group consisting in the diaziridines, the triazoles, the triazines and the tetrazines.
8. The propellant powder according to any one of claims 1 to 7, characterized in that said composition also comprises a pulverulent nitramine charge.
9. The propellant powder according to claim 8, characterized in that said composition has a weight content of pulverulent nitramine charge between 5% and 40% with respect to the total weight of the composition.
10. A process which makes it possible to reduce the erosive effect and to increase the force of a propellant powder for tube weapons based on nitrocellulose and nitroglycerine, characterized in that an energetic nitrogenous organic compound composed solely of carbon, nitrogen and hydrogen and comprising at least one nitrogenous heterocycle and having an enthalpy of formation greater than 418.7 J/g (+ 100 cal/g) is incorporated to said powder, the composition of which has a nitrocellulose/nitroglycerine weight ratio between 2.5 and 1; said compound being incorporated to such a content that the composition of the powder including it contains between 5% and 50% of said compound and between 50% and 95% of nitrocellulose + nitroglycerine, with respect to the total weight of the composition.