Abstract:
Embodiments of systems and methods for improved cleaning of a firearm barrel are provided. Generally, a system according to the present invention includes a cleaning head having a cleaning implement coupled to a shank, which provides at least one radial engagement surface and at least one longitudinal engagement surface. The system may further include a cleaning rod adapted to engage the cleaning head in an at least partially overlapping or surrounding engagement. A method according to the present invention includes the steps of inserting a cleaning head into the breech end of a firearm barrel, engaging the head with a cleaning rod, pushing the head through the barrel and retracting the cleaning rod from the barrel, wherein during the retracting step, the head is disengaged from the rod.

Description:
RELATED APPLICATIONS 
     This application is a divisional of application Ser. No. 12/587,732 filed 13 Oct. 2009 (now U.S. Pat. No. 8,302,342). 
    
    
     BACKGROUND OF THE INVENTION 
     Embodiments of the present invention relate generally to cleaning implements and more particularly to cleaning implements used in cleaning a barrel of a firearm. 
     Barrel cleanliness is extremely important to firearm users. A clean firearm barrel is a prerequisite to consistent accuracy and also safety. Conversely, barrel obstructions decrease the accuracy of a fired projectile and, in extreme situations, can pose a real safety hazard. While safety is important to all firearm users, accuracy is especially desirable in the field of competitive marksmanship. In the field of competitive marksmanship, a firearm is expected to perform in a consistent manner. To maintain such desirable consistency, a marksman may clean his or her firearm as frequently as after every four or five rounds of ammunition, or even after every round of ammunition, fired through the barrel. 
     Typically, the barrel of a firearm, or gun, is cleaned by running a rod with an attached cleaning implement, such as a brush, a swab, or a slotted cleaning head with a cloth patch inserted therethrough, from the muzzle end of the barrel to the breech end of the barrel, or vice versa depending on the type of firearm to which the barrel is attached. Sometimes, the cleaning implement is oscillated to and fro through or within the barrel, as if to scrub particulates from the barrel sidewalls. Furthermore, prior cleaning implements may, after having been inserted into the barrel through the muzzle end, be completely or partially withdrawn from the muzzle end before being reinserted completely into the barrel. 
     Some prior devices have been developed for so-called breech-to-muzzle cleaning of a gun barrel, both for open breech firearms, such as bolt or break action guns, and for closed breech firearms, such as automatic and semi-automatic guns having action and assemblies located near the breech. For instance, Rambo, in U.S. Pat. No. 5,815,975, discloses a breech-to-muzzle cleaning apparatus for use with exposed breech barrels such as those on a break action or lever action firearm, the apparatus including a receptacle for particulates and cleaning patches. Further, Hayes, in U.S. Pat. No. 5,934,000, discloses a pull-through breech-to-muzzle cleaning apparatus for use with semi-automatic or other slide action firearm, such as a pump action. 
     An open breech firearm was usually cleaned in the following manner. A cleaning implement was placed in a generally longitudinally fixed coaxial arrangement with a cleaning rod, such as by being threadably engaged therewith. The cleaning rod had a handle that swiveled or rotated to allow the rod and attached cleaning implement to rotate to follow the rifling formed into the inside surface of the barrel. Known cleaning implements were brushes, swabs or cloth patches mounted on jags or slotted heads. The implement was usually wetted with a cleaning solvent. While unidirectional cleaning is possible with prior devices, it is extremely cumbersome and time consuming because of the longitudinal fixation of the cleaning implement to the rod. 
     Although prior devices have been developed for desired barrel cleaning, there remains room for improvement in the art of firearm maintenance for systems and methods for barrel cleaning having a minimized impact on firearm accuracy. 
     SUMMARY OF THE INVENTION 
     Embodiments of the present invention include systems and methods for barrel cleaning having a minimized impact on firearm accuracy. It has been discovered that extensive cleaning of a firearm barrel, while thought to maintain consistency and safety, may unexpectedly lead to decreased accuracy if the cleaning procedure is not carried out properly. For instance, it has been found that significant, though largely visibly imperceptible with the naked eye, deformation of the muzzle end, or crown formed therein, of a barrel results from the insertion, especially repeated insertion, of a cleaning implement or a portion thereof, through the muzzle end and into the barrel. The crown is a critical portion of the barrel as far as accuracy is concerned. If the crown is uneven, the high pressure gas that propels a bullet through the barrel will escape unevenly, causing the bullet to oscillate while in its flight path after exiting the barrel, thereby degrading accuracy. The manipulation of a cleaning implement back into the barrel from the muzzle end to the breach end has been discovered to wear the crown unevenly. The wear is thought to be increased where the cleaning implement has been fouled with gun powder and glass powder residue from the cartridge primer from being passed through the barrel from breech to muzzle first. 
     A firearm barrel cleaning apparatus according to the present invention includes a cleaning head sized to be inserted into the barrel. The cleaning head extends between a first cleaning end and a second control end. The cleaning head includes a cleaning implement coupled to a shank. The shank extends from the control end towards the cleaning end and includes a shank body formed about a shank axis and extending along a shank length. The shank body provides at least one radial engagement surface extending from said control end towards said cleaning end, the at least one radial engagement surface being formed along at least a portion of the shank length at least substantially parallel to the shank axis. The shank body also provides at least one longitudinal engagement surface disposed at an oblique angle with respect to the shank axis. The longitudinal engagement surface may be a substantially planar surface that forms the control end of the cleaning head. 
     According to an aspect of a cleaning head according to the present invention, the cleaning implement extends from the cleaning end towards the control end. 
     According to an aspect of a cleaning head according to the present invention, the at least one radial engagement surface extends along a majority of the shank length. 
     According to an aspect of a cleaning head according to the present invention, the shank body includes a plurality of radial engagement surfaces, at least one of which may be substantially planar. 
     According to an aspect of a cleaning head according to the present invention, at least one radial engagement surface may be a perimeter of a reentrant bore formed into the shank body from the second control end. The reentrant bore may be formed along a majority of the shank length. A cross-section of the reentrant bore may encompass a mathematical convex set of points, where the cross-section is taken perpendicular to the shank axis. Alternatively or additionally, a cross-section of the reentrant bore may encompass a mathematical concave set of points, where said cross-section is taken perpendicular to the shank axis. 
     According to an aspect of a cleaning head according to the present invention, the cleaning implement may include a brush. The brush may include a helical frame and a plurality of bristles, which may be formed of brass, extending radially from and supported by the helical frame. 
     According to an aspect of a cleaning head according to the present invention, the cleaning implement may include a cleaning patch, such as a cotton cleaning patch. In combination with the cleaning patch, the cleaning implement may further include a slotted tip through which the cleaning patch is inserted, or a cleaning jag about which the cleaning patch is disposed. 
     According to an aspect of a cleaning apparatus according to the present invention, a longitudinal cleaning rod may be provided to engage the cleaning head. The cleaning rod extends between and includes a handle end and a control end. The control end is formed in a mating configuration to the at least one engagement surface provided on the cleaning head. 
     A method of cleaning a firearm barrel, which has a breech end, a muzzle end and a bore extending therethrough, according to the present invention includes the step of providing a cleaning head including a cleaning implement coupled to a shank and providing a cleaning rod. The cleaning implement, followed by the shank, is inserted into the bore of the firearm barrel from the breech end, thereby establishing a frictional contact between the cleaning implement and the barrel. The shank is then engaged by the cleaning rod, preferably in an at least partially overlapping or surrounding engagement. After engaging the shank with rod, the cleaning implement is pushed at least partially or even completely through the bore towards the muzzle end in a first cleaning direction. After pushing the cleaning implement at least partially through the bore, the cleaning rod is pulled in a second retraction direction, which is at least substantially opposite the cleaning direction. During the pulling step, a first sum of all of a first set of forces acting on the cleaning head in the cleaning direction is greater than a second sum of all of a second set of forces acting on the cleaning head in the retraction direction, thereby causing disengagement of the cleaning rod from the cleaning head. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a first embodiment of a firearm barrel cleaning head according to the present invention. 
         FIG. 2A  is a perspective view of a first alternative cleaning implement. 
         FIG. 2B  is a perspective view of a second alternative cleaning implement. 
         FIG. 2C  is a perspective view of a third alternative cleaning implement. 
         FIG. 3  is a partial cross-section view taken along line  3 - 3  of  FIG. 1 . 
         FIG. 4A  is a cross-section taken along line  4 - 4  of  FIG. 1 . 
         FIG. 4B  is a first alternative cross-section taken along line  4 - 4  of  FIG. 1 . 
         FIG. 4C  is a second alternative cross-section taken along line  4 - 4  of  FIG. 1 . 
         FIG. 4D  is a third alternative cross-section taken along line  4 - 4  of  FIG. 1 . 
         FIG. 4E  is a fourth alternative cross-section taken along line  4 - 4  of  FIG. 1 . 
         FIG. 5  is a partial cross-section of a first alternative shank according to the present invention. 
         FIG. 6A  is a cross-section taken along line  6 - 6  of  FIG. 5 . 
         FIG. 6B  is a first alternative cross-section taken along line  6 - 6  of  FIG. 5 . 
         FIG. 6C  is a second alternative cross-section taken along line  6 - 6  of  FIG. 5 . 
         FIG. 6D  is a third alternative cross-section taken along line  6 - 6  of  FIG. 5 . 
         FIG. 6E  is a fourth alternative cross-section taken along line  6 - 6  of  FIG. 5 . 
         FIG. 7A  is a perspective view of a first embodiment of a cleaning rod according to the present invention. 
         FIG. 7B  is a magnified view of a portion of the embodiment of  FIG. 7A . 
         FIGS. 8A-8D  depict various steps of a cleaning method according to the present invention. 
         FIG. 8E  presents a final step for use in connection with the method of  FIGS. 8A-8D . 
         FIG. 8F  depicts an alternative final step for use in connection with the method of  FIGS. 8A-8D . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Although the disclosure hereof is detailed and exact to enable those skilled in the art to practice the invention, the physical embodiments herein disclosed merely exemplify the invention which may be embodied in other specific structures. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims. 
     Turning now to the figures,  FIG. 1  provides an embodiment of a cleaning head  100  according to the present invention. Generally, the cleaning head  100  extends between a first, cleaning end  102  and a second, control end  104 . A part of the cleaning head  100  is a cleaning implement  110 , which, although it may be disposed between and spaced from the first end  102  and the second end  104 , preferably extends from the first end  102  towards the second end  104 . Extending from the second end  104  towards the first end  102  is a control shank  120 . 
     The cleaning implement  110  may include a brush  112 . Alternatively, the cleaning implement  110  may include a swab or mop (see  FIG. 2A ), or a cleaning jag (see  FIG. 2B ) or slotted tip (see  FIG. 2C ) cooperating with a cleaning patch as are generally known in the art of barrel cleaning. If a brush  112  is provided as the cleaning implement  110 , the brush  112  may include a generally longitudinal bristle frame, such as a helical steel or brass wire frame  114 . Secured to and supported by the bristle frame  114  is a plurality of bristles  116  extending radially outwardly from the frame  114 . The bristles  116  may be formed of a material that is softer than expected firearm barrel material. A preferred material for the bristles  116  is brass. Alternative materials may be used to form the bristles  116 , such as phosphor bronze or a resinous plastic material sold under the brand name of Tynex® by E.I. DuPont de Nemours and Company, located at Wilmington, Del. 
       FIGS. 2A ,  2 B and  2 C depict alternative cleaning implements  110 , as mentioned above.  FIG. 2A  provides an embodiment of a cleaning implement  110  in the form of a swab or mop  212  mounted to a swab support shaft  214 , which is then coupled to a shank  120 . The swab  212  is preferably a cotton swab and the support shaft  214  is preferably aluminum.  FIG. 2B  provides an embodiment of a cleaning implement  110  in the form of a cleaning jag  312  supported on a jag shaft  314 , which is then coupled to a shank  120 , in cooperation with a cotton cleaning patch  316 . The jag  312  is preferably made of brass and preferably integrally formed with the jag shaft  314 .  FIG. 2C  provides an embodiment of a cleaning implement  110  in the form of a slotted tip  412  supported on a tip shaft  414 , which is then coupled to a shank  120 , in cooperation with a cotton cleaning patch  416 . The slotted tip  412  is preferably made of brass and preferably integrally formed with the tip shaft  414 . 
     Whichever cleaning implement  110  is utilized, the implement  110  preferably has a longitudinal implement axis  111 , which may form an axis of symmetry. 
     The control shank  120  is preferably formed as a longitudinal body about a shank axis  121 . The shank  120  has a shank length  122 , which extends from the second end  104  of the cleaning head  100  to a mounting end  124  of the shank  120 . Extending along at least a portion, and preferably a majority, of the shank length  122  is at least one radial engagement surface  126 , which is formed preferably parallel to the shank axis  121 . The shank  120  also preferably includes at least one longitudinal engagement surface  127 , which is formed at an oblique angle relative to the shank axis  121 . The radial engagement surface(s)  126  may be formed inside the shank  120 , as shown in  FIG. 3  and  FIGS. 4A-4E , such as by forming a portion of a perimeter of a reentrant bore  128  formed into the shank  120  from the second end  104 . While it has been stated that the engagement surface(s)  126  are preferably formed at least substantially parallel to the shank axis  121 , where an engagement surface  126  is provided inside the shank  120 , that surface  126  may slope towards the shank axis  121  from a first point  126   a  on the surface  126  located near the second end  104  to a second point  126   b  on the surface  126  located further from the second end  104  than the first point  126   a . The reentrant bore  128  may have a cross-section, taken at least substantially perpendicular to the shank axis  121 , in which the bore  128  surrounds a mathematical convex set of points, such as those cross-sections shown in  FIGS. 4A-4D . Alternatively, the reentrant bore  128  may have a cross-section, taken at least substantially perpendicular to the shank axis  121 , in which the bore  128  surrounds a mathematical concave set of points, such as the cross-section shown in  FIG. 4E . 
     Alternatively or additionally, one or more of the engagement surfaces  126  may be formed on the outside of the shank  120 , as shown in  FIG. 5  and  FIGS. 6A-6E . While it has been stated that the engagement surface(s)  126  are preferably formed at least substantially parallel to the shank axis  121 , where an engagement surface  126  is provided on the outside of the shank  120 , that surface  126  may slope away from the shank axis  121  from a first point  126   a  on the surface  126  located near the second end  104  to a second point  126   b  on the surface  126  located further from the second end  104  than the first point  126   a.    
     The longitudinal engagement surface  127  may be the second end  104 , or may be provided in addition thereto. If the longitudinal engagement surface  127  is provided in addition to or spaced from the second end  104 , the at least one longitudinal engagement surface  127  meets at least one radial engagement surface  126  at preferably an inside angle  129 . The longitudinal engagement surface  127  provides a surface adapted to engage a rod longitudinal engagement surface  527 , as is described below. 
     The cleaning implement  110  is coupled to the mounting end  124  of the shank  120 , preferably to at least substantially align the implement axis  111  to the shank axis  121 . The cleaning implement  110  may be fastened to the shank  120 , may be adhered to the shank  120 , may be mechanically engaged therewith, such as by threads, or a portion of the cleaning implement  110  may be integrally formed with the shank  120 . 
     While a cleaning head  100  may be simply pushed through a firearm barrel by pushing against the control end  104  thereof, a cleaning rod is preferably provided to engage the cleaning head  100  in an at least partially overlapping or surrounding relationship.  FIGS. 7A and 7B  depict an embodiment of a cleaning rod  500  according to the present invention. The cleaning rod  500  extends between a control end  510  and a cleaning end  520 . Provided at or near the control end  510  is a handle  512 , which may be formed in a general T-shape, as shown. The handle  512  may be fixedly mounted on the rod  500 , or it may be rotatably mounted on the rod  500 , as is known, so as to allow the handle  512  to rotate about the rod axis  521 . The cleaning end  520  of the cleaning rod  500  is formed about a rod axis  521  so as to matingly engage at least a portion of the cleaning head shank  120  in an overlapping or surrounding relationship. This overlapping or surrounding relationship may occur in one of two ways: a portion of the cleaning end  520  of the rod  500  may overlap or surround a portion of the shank  120 , or a portion of the shank  120  may overlap or surround a portion of the cleaning end  520 . One way to accomplish this is a male-female relationship between a portion of the shank  120  and the control end  520  of the cleaning rod  500 , with one portion of the relationship (male or female) being provided on the shank  120  and the other portion (female or male) being provided on the rod  500 . Regardless of the arrangement, the shank  120  and control end  520  must be sized so as to accommodate preferably frictionless insertion into a predetermined firearm barrel. 
     In the depicted embodiment  500 , the cleaning end  520  includes at least one rod radial engagement surface  526  and at least one rod longitudinal engagement surface  527 . The at least one rod radial engagement surface  526  is formed preferably at least substantially parallel to the rod axis  521 . The cleaning end  520  also preferably includes at least one longitudinal engagement surface  527 , which is formed at an oblique angle relative to the rod axis  521 . The radial engagement surface(s)  526  may be formed on the outside of the control end  520 , as shown in  FIG. 7B . While it has been stated that the engagement surface(s)  526  are preferably formed at least substantially parallel to the rod axis  521 , where an engagement surface  526  is provided on the outside of the control end  520 , that surface  526  may slope towards the shank axis  521  from a first point  526   a  on the surface  526  located near the cleaning end  520  to a second point  526   b  on the surface  526  located further from the cleaning end  520  than the first point  526   a.    
     Additionally or alternatively, the radial engagement surface(s)  526  may form a portion of a perimeter of a reentrant bore (not shown) formed into the cleaning end  520 , in a similar fashion to the bore  128  shown with respect to the first cleaning head  100 . While it has been stated that the engagement surface(s)  526  are preferably formed at least substantially parallel to the rod axis  521 , where an engagement surface  526  is provided inside the cleaning end  520 , that surface  526  may slope away from the rod axis  521  from a first point  526   a  on the surface  526  located near the cleaning end  520  to a second point  526   b  on the surface  526  located further from the cleaning end  520  than the first point  526   a . The reentrant bore (not shown), like the reentrant bore  128  formed into the shank  120 , may have a cross-section, taken at least substantially perpendicular to the rod axis  521 , in which the bore surrounds a mathematical convex set of points, similar to those cross-sections shown in  FIGS. 4A-4D . Alternatively, the reentrant bore may have a cross-section, taken at least substantially perpendicular to the shank axis  521 , in which the bore surrounds a mathematical concave set of points, similar to the cross-section shown in  FIG. 4E . 
     The longitudinal engagement surface  527  may be the cleaning end  520 , or may be provided in addition thereto. If the longitudinal engagement surface  527  is provided in addition to or spaced from the cleaning end  520 , the at least one longitudinal engagement surface  527  meets at least one radial engagement surface  526  at preferably an inside angle  529 . The longitudinal engagement surface  527  provides a surface adapted to engage a shank longitudinal engagement surface  127 , as is described above. 
       FIGS. 8A-8F  depict various steps in a method of cleaning a firearm barrel  600  according to the present invention. A method according to the present invention generally provides unidirectional firearm barrel cleaning, preferably in the breech-to-muzzle direction. The insertion of a cleaning implement into the muzzle end of a firearm barrel has been discovered to alter accuracy much more than previously thought. In a method according to the present invention, a firearm barrel  600  and a cleaning head  100  are provided. The cleaning head  100  includes a cleaning implement  110  coupled to a shank  120 . A cleaning rod  500  is also provided. The cleaning implement  110  is inserted into a breech end  602  of a bore formed in a provided firearm barrel  600 , followed by the shank  120 . The breech end  602  is the end of the barrel  600  that is, or is adapted to be, positioned closer to the firearm action or firing mechanism  604 , and a muzzle end  606  of the barrel  600  is the end of the barrel  600  that is, or is adapted to be, positioned further from the firearm action or firing mechanism  604 . The cleaning implement  110  is sized so as to frictionally engage the perimeter of the bore formed in the barrel  600 , as is generally now known in the art. 
     The rod  500  is engaged with the shank  120  on the cleaning head  100 . This engagement is preferably an at least partially overlapping or surrounding engagement extending preferably along a majority of the shank length  122 . The engagement can be performed prior to or after the insertion of the cleaning implement  110  into the barrel. After the rod  500  and shank  120  are engaged, preferably in the at least partially overlapping or surrounding engagement, the cleaning implement  110  is pushed at least partially through, and preferably completely through, the bore towards the muzzle end  606  of the barrel  600  in a first cleaning direction  701 . After the cleaning implement  110  is pushed at least partially through the bore of the barrel  600 , the cleaning rod  500  is pulled in a second retraction direction  702 , which is at least substantially opposite the first cleaning direction  701 . 
     During the pulling of the rod  500  in the retraction direction  702 , a first sum of all of a first set of forces, F(c), acting on the cleaning head  100  in the cleaning direction  701  is greater than a second sum of all of a second set of forces, F(r), acting on the cleaning head  100  in the retraction direction  702 . Because F(c) is greater than F(r), the cleaning rod  500  is disengaged from the cleaning head  100 . Generally, F(c) may include only frictional force acting on the cleaning head  100  by the barrel  600  or mechanical forces applied to the cleaning head  100 , such as by pulling, through the muzzle end  606  of the barrel  600 , a string (not shown) fastened to the first end  102  of the cleaning head  100  or by applying, through the breech end  602  of the barrel  600 , a pushing force against the second end  104  of the cleaning head  100 . Alternatively, F(c) may include both barrel frictional force and force(s) mechanically applied to the head  100 . An additional mechanical force may be included in F(c) that is established by the physical abutment of the cleaning implement  110  with the muzzle end  606  of the barrel  600  after the cleaning implement  110  has been pushed partially out of the muzzle end  606  or completely through the barrel  600 . Generally, F(r) may include frictional forces caused by contact between the rod  500  and the shank  120  and/or mechanical forces such as desired shank retention forces that may be provided by a spring loaded ball bearing (not shown) included near the cleaning end  520  of the rod  500 , where the ball bearing acts in cooperation with the shank  120  to maintain the shank  120  and rod  500  in a mechanical engagement of a desired force. 
     In any event, the cleaning head  100  is at least substantially, and preferably completely, prevented from moving in the retraction direction  702  by the forces F(c) acting in the cleaning direction  701  while the cleaning rod  500  is moved in the retraction direction  702 . In this manner, the cleaning head  100  is prevented from even accidentally being pulled back across the crown at the muzzle end  606 . For instance, as shown in  FIG. 8E , the cleaning head  100  may be caused to fall off of the cleaning rod  500  in a release direction  703  simply by the force of gravity. Alternatively, as shown in  FIG. 8F , for some reason, the cleaning head  100  may be retained on the cleaning rod  500  against the force of gravity, so the cleaning head  100  may be drawn back against, but not into, the muzzle end  606  of the barrel  600 , thereby increasing F(c) greater than F(r) so as to disengage the head  100  from the rod  500 . 
     The foregoing is considered as illustrative only of the principles of the invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the invention, which is defined by the claims.