METHOD AND CLEANING AGENT COMPOSITION FOR CLEANING THE BARREL OF A GUN

Abstract: The invention relates to a method for cleaning the barrel of a firearm, whereby a foam containing an agent that removes bullet residue is applied into the firearm barrel to be cleaned, the foam is allowed to act for 0.1 - 30 minutes, whereupon the foam is removed from the barrel.

Description: Method and cleaning agent composition for cleaning the barrel of a gun. The present invention relates to a method for cleaning the barrel of a firearm as presented in claim 1. The barrel of a firearm has to be cleaned at regular intervals to remove the remnants of bullets and combustion residue such as soot, powder and burnt grease, accumulated in the barrel. In this context, bullet remnants means the metal residue left in the barrel from bullets, such as, in the case of commonly used bullets containing copper, residue of copper, possible copper compounds and other alloyed metals, e.g. copper and zinc residue and, in the case of lead bullets, lead residue. Various methods and cleaning agents for the cleaning of a gun barrel are known. However, current cleaning methods often involve mechanical cleaning by scrubbing the barrel with a hard brush, such as a bronze brush. For example, in a commonly used cleaning method the cleaning agent contains aluminium particles which scrub off impurities from the barrel surface du¬ ring mechanical cleaning. Mechanical scrubbing is a laborious and time- consuming operation. Naturally it also causes wear of the barrel surface, thus shortening the service life of the firearm. To remove the copper residue left in the bar¬ rel from copper bullets, cleaning agents acting chemi¬ cally on copper have also been tried. This type of cleaning agents usually contain ammonia, and the prob¬ lem has been that ammonia is very volatile, i.e. the cleaning agent quickly becomes ineffective as the ac¬ tive component evaporates. Furthermore, when such cleaning agents are used, the barrel must nevertheless be cleaned mechanically as well, so they do not elimi¬ nate the drawbacks associated with mechanical clea- ning. Moreover, the evaporating gases are detrimental and undesirable. EP specification 75 113 presents a composition of substances that contains ammonia or amine compounds mixed in a gel to prevent evaporation. In addition, the commonest cleaning agents currently used are relatively expensive. The object of the present invention is to eliminate the drawbacks referred to above. A special object of the invention is to pro- duce an effective cleaning method of a new type that reduces the need for mechanical cleaning and thus sig¬ nificantly extends the service life of the barrel. A further object of the invention is to pro¬ duce a new type of cleaning method that is faster and more user- friendly than earlier methods. As for the features characteristic of the in¬ vention, reference is made to the claims. The invention is based on the unexpected ob¬ servation made during investigations that bullet resi- due can be removed by using a foam that, in the case of bullets containing copper, contains an alkaloamine and, in the case of bullets containing lead, a nitrate salt. Thanks to the invention, a method has now been discovered that makes it possible to effectively and quickly remove the metal residue left by bullets in a barrel, without damaging the steel of the barrel. In the method of the invention, ammonia can also be used for the cleaning of a barrel because the foam prevents evaporation of ammonia, so the cleaning agent does not lose any of its effectiveness. For the first time, the present invention produces a firearm cleaning method that uses a foam containing substances that remove bullet residue. The foam to be used can be produced by using a tenside. The tenside may be any commonly used, foam-producing surface-active substance, such as coconut diethanola- mide. Further, nitrate salt has now been used for the first time as a material that chemically removes bullet residue. It was observed during investigations carried out that lead residue in a barrel reacts due to nitrate salt in a way that allows the lead to be removed from the barrel surface without mechanical scrubbing. The nitric salt used is preferably an inor¬ ganic nitrate, such as alkaline nitrate, alkaline earth nitrate or ammonium nitrate, especially sodium nitrate. In the method of the invention, the cleaning can be performed by using any substance that forms a foam, preferably a consistent foam, that contains e.g. exclusively nitrate salt, in which case it is appli¬ cable for the cleaning of firearms using lead bullets. The pH of the nitrate salt solution is preferably ad¬ justed to an alkalic value if necessary. However, e.g. in the case of sodium nitrate, no pH adjustment is needed. There is no indication that, when used in the manner described, nitrates cause wear of the steel ma- terial of the barrel. The reaction product is removed automatically from the barrel surface, or it can be removed by using only a soft felt plug, i.e. without actual mechanical scrubbing. Thus, when the method of the invention is used, bullet residue can be effecti- vely removed from the barrel by wiping it with a mate¬ rial or plug commonly used for the cleaning of fire¬ arms, without damaging the steel material of the bar¬ rel. In an embodiment of the method of the inven- tion, preferably a consistent foam containing an al- kanolamine and/or a nitrate salt is used, in which ca¬ se the method is applicable for the cleaning of both firearms using lead bullets and firearms using cop¬ per/copper compound bullets. In addition to its prima- ry purpose in the method of the invention, the alkano- lamine can also be used for the adjustment of the pH of the solution to an alkalic value in connection with solutions containing a nitrate salt. The alkanolamine is preferably monoethanolamine or diethanolamine or a compound of these, especially monoethanolamine. In the cleaning method of the invention, a foam is used that contains about 1 - 80 w-%, prefera¬ bly about 20 - 70 w-% nitrate salt, such as sodium nitrate, and/or about 1 - 70 w-%, preferably about 1 - 30 w-%, e.g. 2 - 25 w-% alkanolamine, such as monoet¬ hanolamine or diethanolamine. In the method of the invention, a foam is us¬ ed that preferably additionally contains an organic solvent for the removal of combustion residue such as soot, gunpowder remnants and/or burnt grease. For this purpose, any solvent or solvents, especially a water- soluble/mixable solvent, may be used. In an especially advantageous case, the composition contains under 50 w-%, e.g. 1 - 15 w-% methylpyrrolidone and/or under 50 w-%, e.g. 1 - 15 w-% butoxyethanol, which have proved to be effective in removing combustion residue. The amount of tenside used in the cleaning method is e.g. under 50 w-%, e.g. about 0.1 - 25 w-% of the composition, depending on the intended applica¬ tion. The foam used in the cleaning method may further contain about 1 - 90 w-% added water. By va¬ rying the amount of water, it is possible e.g. to ad¬ just the concentrations of the active substances as desired. The amount of water added may be e.g. 5 - 60 w-%. In a preferable embodiment, an amount of un¬ der 15 w-%, e.g. about 0.1 - 3 w-%, of sodium salt of m-nitrobenzenesulfonic acid has been added to a compo¬ sition containing alkanolamine to assist in removing from the barrel surface the reaction products formed by residue from bullets containing copper. The composition used in tr.- method of the in¬ vention may additionally contain an amount of about 0.1 - 30 w-%, e.g. 1 - 10 w-%, of a barrel protecting substance, such as commonly known arms oil or prefera¬ bly so-called cutting lubricant, which may be of semi- synthetic or synthetic type and which prevents copper from sticking to the barrel. The agent used for barrel treatment may be a water-mixable substance or it can be emulsified in water using e.g. a tenside and/or solvent, such as butoxyethanol . The composition of substances used in the method of the invention can be implemented in any sui¬ table form. Preferably the composition is in the form of a foaming liquid or, suitably, in the form of a spray sprayable as a foam, in which case it is packed in a container equipped to produce a spray, together with propellants if required. The composition may also contain an agent that increases viscosity. In the following, the invention is described in greater detail by the aid of examples, which are only intended to illustrate the invention without li- miting it. Example 1: Producing a composition of substances for use in the cleaning method of the invention. A cleaning solution composed according to one of the following alternatives is prepared: w-% prefer¬ composition Components red A B C D E coconut diethanol- amide 0.1-50 4 25 2 3 monoethanolamine 0-70 1-30 25 2 15 71 sodium nitrate 0-70 20-70 40 20 70 40 methylpyrrolidone 0-30 1-15 5 15 5 10 5 1-butoxyethanol 0-30 1-15 5 15 5 10 5 sodium salt of m-nitrobenzene- sulfonic acid 0-30 0.1-3 1 3 2 10 semi-synthetic cutting lubricant 0-30 1-10 10 10 10 10 water added 0-60 1-30 10 10 12 10 When compounding the components, the sodium nitrate is solved in the water added. It can also be added to other components in the form of a rich water solution. Instead of monoethanolamine, other alkanola- mines can also be used, such as diethanolamine. When the composition is produced in the form of a foaming liquid, the formulation is performed by using a tensi¬ de in an amount of e.g. about 0.1 - 30 w-%. When the composition is produced in the form of a spray, the amount of tenside used is e.g. 0.1 - 4 w-%. The con- centrations of active components are selected e.g. on the basis of the length of time tne cleaning agent is to be allowed to act in the barrel. This action time may vary e.g. between 0.1 - 30 mm., whereupon the composition is removed by using a plug of a medium, e.g. a felt plug. The finished composition has an alkalic pH value. The cleaning method of the invention is less hazardous to the user and the environment than earlier methods and the composition emits no toxic gases as compared with previous compositions. Moreover, consis¬ ting of cheap components, it is advantageous in res¬ pect of cost. The composition used does not suffer any loss of efficiency during storage or use. Furthermore, the composition used in the method protects the bar- rel, and the addition of cutting oil has the effect that a smaller amount of bullet residue, such as cop¬ per, sticks to the barrel surface. Generally, the cleaning method of the inven¬ tion is applicable for the cleaning of the barrel part of a firearm of any type and any size. Example 2: An experiment was carried out to test the ef¬ fectiveness and applicability of a cleaning method as provided the invention, designed for firearms using copper/copper compound bullets. Composition of the foam used in the method Components w-% monoethanolamine ca.25 methylpyrrolidone ca. 5 1-butoxyethanol ca. 5 sodium salt of m-nitro- benzenesulfonic acid ca . 1 coconut diethanolamide ca . 4 water added ca . 50 semi-synthetic cutting lubricant ca. 10 The composition was prepared in the form of a spray. To clean a firearm, the foaming alkalic compo¬ sition was sprayed into the barrel and allowed to act for ca. 10 min., whereupon it was removed by pushing a felt plug through the barrel. The firearm cleaning method was tested in field conditions during half a year. It was establis¬ hed that the cleaning method worked in cold and hot weather. Moreover, the method was found to be effecti¬ ve and easy to use. In comparing a barrel cleaned by the method of the invention was compared with a barrel cleaned by the traditional mechanical method, the barrels were inspected using an endoscope and it was established that the barrel treated by the method of the invention was in a considerably better condition, i.e. it showed less wear and burn damage, than the reference barrel. It is estimated that, by using the cleaning method of the invention, the service life of a firearm is exten¬ ded by about 50 %.

Claims: CLAIMS 1. Method for cleaning the barrel of a fire¬ arm, characterized in that a foam containing an agent that removes bullet residue is applied into the fire- arm barrel to be cleaned, the foam is allowed to act for 0.1 - 30 minutes, whereupon the foam is removed from the barrel. 2. Cleaning method as defined in claim 1, characterized in that the agent is allowed to be acti- ve in the barrel for 1 - 20 minutes. 3. Cleaning method as defined in claim 1 or 2, characterized in that the foaming agent used is a tenside. 4. Cleaning method as defined in any one of claims 1 - 3, characterized in that the foaming agent used is coconut diethanolamide. 5. Cleaning method as defined in any one of claims 1 - 4, characterized in that the proportion of foam material is under 50 w-%, e.g. 0.1 - 25 w-%, of the whole amount of the composition. 6. Cleaning method as defined in any one of claims 1 - 5, characterized in that the foam material is introduced into the firearm barrel in liquid state and foamed by drawing a plug of a medium through the barrel. 7. Cleaning method as defined in any one of claims 1 - 6, characterized in that the foam is spray¬ ed into the firearm barrel from a spray bottle. 8. Cleaning method as defined in claim 7, characterized in that the foam is sprayed from a spray bottle through an elastic sealing fitted on the end of the barrel. 9. Cleaning method as defined in any one of claims 1 - 8, characterized in that the substance used for removing bullet residue is an alkanolamine and/or an inorganic nitrate. 10. Cleaning method as defined m any one of claims 1 - 9, characterized in that the alkanolamine used is monoethanolamine and/or diethanolamine. 11. Cleaning method as defined in any one of claims 1 - 10, characterized in that the nitrate salt used is an inorganic nitrate, such as sodium nitrate. 12. Cleaning method as defined in any one of claims 1 - 11, characterized in that the method mvol- ves the use of a foam containing a solvent designed to remove combustion residue. 13. Cleaning method as defined in any one of claims 1 - 12, characterized m that ..t involves the use of a foam that contains under 50 w-%, preferably 1 - 15 w-% methylpyrrolidone and/or under 50 w-%, prefe¬ rably 1 - 15 w-% butoxyethanol. 14. Cleaning method as defined in any one of claims 1 - 13, characterized in that it involves the use of a foam that contains about 0 - 90 w-% water ad- ded. 15. Cleaning method as defined m any one of claims 1 - 14, characterized in that it involves the use of a foam that, in conjunction with tne alkanola¬ mine, contains under 5 w-% sodium salt of ir- nitrobenzenesulfonic acid. 16. Cleaning method as defined m any one of claims 1 - 15, characterized in that it involves the use of a foam that contains a substance lubricating and protecting the firearm barrel, sucn as semi- syntnetic or synthetic cutting lubricant or arms oil. 17. Composition of cleaning agents for the cleaning of the barrel of a firearm, said composition containing a substance removing pullet residue, cha¬ racterized in that the composition contains a tenside, and that the substance removing bullet residue is an alkanolamine and/or a nitrate salt, and that the com- position is in the form of a foam according to any one of claims 1 - 16.

Inventors: PAANANEN MARKKU, PAANANEN, MARKKU
Applicants: KOIVULUOMA MARJA, PAANANEN MARKKU, KOIVULUOMA, MARJA, PAANANEN, MARKKU
Application year: 1995
Main classification: F41A29
IPC codes: C11D1, C11D3, C11D11, F41A29