US2765740A - Barrel cleaning shell for firearms - Google Patents

Description

Oct. 9, 1956 J. w. NORMAN BARREL CLEANING SHELL FOR FIREARMS Filed Oct. 12 1951 INVENTOR. James 14 4 0/7 14 BY BARREL CLEANING SiELL FOR FIREARMS Jones W. Norman, ()ttawa, 111.

Application October 12, 1951, Serial No. 250,988

1 Claim. (Cl. 10239) This invention relates to shells for cleaning the bores of firearm barrels and more particularly to a shell for cleaning the bore of a large bore firearm, such as a shotgun.

It is among the objects of the invention to provide an improved bore cleaning shell for use in large bore firearms, such as shotguns, which moves a cleaning pad or wad through the bore of the barrel after the propelling powder charge has passed through the bore to leave the bore in a clean condition; which is of substantially the same size and shape as standard shotgun shells and can be conveniently provided in sizes to fit different standard bores; and which is simple and durable in construction, economical to manufacture, and eificient and effective in use.

Other objects and advantages will become apparent from a consideration of the following description and the appended claim in conjunction with the accompanying drawing wherein:

Figure l is a side elevational view of a bore cleaning firearm shell illustrative of the invention;

Figure 2 is a longitudinal cross sectional view on the line 22 of Figure 1;

Figure 3 is a transverse cross sectional view on the line 33 of Figure 2;

Figure 4 is a transverse cross sectional view on the line 44 of Figure 2;

Figure 5 is a transverse cross sectional view on the line 55 of Figure 2;

Figure 6 is a longitudinal cross sectional view of a somewhat modified form of the device;

Figure 7 is a partly cross sectional view of a core assembly constituting a component of the modified form shown in Figure 6;

Figure 8 is a composite plan view of the blanks from which the core element is manufactured; and

Figure 9 is a cross sectional view on an enlarged scale on the line 9-9 of Figure 6.

With continued reference to the drawing, the shell has the size, shape and general appearance of an ordinary shotgun shell and comprises, in general, a cylindrical casing lil formed of paper or other suitable material and dimensioned to fit a shell chamber corresponding to a selected standard bore, a cap or head 11 secured to the casing at one end of the latter and closing such one end of the casing, a primer 12 extending through the head into the casing, a bore cleaning wad or pad 13 disposed in the casing adjacent the head and having an aperture therethrough receiving the primer 12, a powder charge 14 disposed in the casing at the side of the cleaning wad 13 remote from the closed end of the head 11, a weight assembly 15 disposed in the casing at the end of the powder charge 14 remote from the cleaning pad 13, wadding 16 secured in the casing at the open end of the latter and resilient tension means 17 extending through the powder charge 14 and connecting the weight assembly to the cleaning wad 13, this tension means having a length, when stretched, somewhat greater than the bore of a gun barrel so that the cleaning wad 13 will be pulled by these tension means through the bore of the barrel after the weight assembly 15 has been propelled out of the bore by the explosion of the powder charge 14.

The head 11 may be conveniently formed of a stamping of sheet metal, such as copper or brass, and has in ice its end wall an aperture receiving the primer 12. The primer is of elongated, somewhat conical shape and is disposed with its larger end received in the aperture of the end wall of the head and extending through a central aperture in the cleaning wad 13 with its inner end in contact with the powder charge 14 at the adjacent end of the latter to ignite the powder charge when the primer is fired.

The cleaning wad 13 comprises two spaced apart and substantially parallel discs 18 and 19 of rigid material with a filling 20 of spongy or compressible material between the discs. The spongy material 20 may be a suitable cotton or felt material and may contain oil or an abrasive, as may be desired.

The weight assembly 15, as illustrated, comprises two spaced apart and substantially parallel discs 21 and 22 of rigid material with a filling 23 of shot, or similar heavy material, between these two discs. The two discs 21 and 22 are connected together by resilient tension members 24 and 25 in the form of coiled wire springs each connected at one end to the disc 21 and at its other end to the disc 22 and extending through the filling 23.

The wadding 16 comprises a disc 26 of substantially rigid material, such as heavy paper, spaced from and substantially parallel to the disc 22 and a filling of compressible or resilient material 27 between the discs 22 and 26, the material 27 being a suitable fibre or felt, such as is ordinarily employed in the wadding of shotgun shells. The entire load is retained in the shell casing 10 by crimping the shell at its open end over the marginal portion of the outer disc 26, as indicated at 28, in a manner well known to the art.

The tension means or members 17 may conveniently comprise coiled wire springs each attached at one end to the disc 21 and the adjacent ends of the springs 24 and 25 and extending at their other ends through the disc 19, the filling 20 and the disc 18 and secured at such ends to the disc 18 at the outer side of the latter. The disc 18 is preferably thickened for reinforcement, as indicated at 29, where the ends of the wire springs 17 extend therethrough.

The springs 17 are preferably formed of a suitable material, such as a tungsten alloy, which will not be materially weakened by the heat of the explosion of the powder charge 14, and which have a strength sufiicient to pull the cleaning wad 13 through the bore of the barrel when the weight assembly 15 is forced out of the bore at the muzzle end of the barrel by the explosion of the powder charge. These springs have a stretched length somewhat greater than the length of the bore, so that the weight assembly can move outwardly of the muzzle end of the barrel sufficiently to permit the gas from the powder charge to escape and lose its pressure before the cleaning wad is moved toward the muzzle end of the bore.

After the weight assembly has moved out of the muzzle end of the gun barrel the springs 24 and 25 will stretch to permit dispersion of the shot filler 23 and somewhat lessen the jerk on the springs 17. The pull exerted on the disc 21 and the adjacent ends of the springs 17 by the shot filling bearing against the adjacent side of the disc 22 and stretching the springs 24 and 25 will, however, be suflicient to pull the cleaning wad entirely through the bore of the gun barrel.

In the modified form of the device illustrated in Figures 6 to 9 inclusive, a unitary core element, generally indicated at 30, is inserted into an empty shell casing 31 of conventional construction to constitute the cleaning shell assembly.

The core element 39 comprises a felt carrier 32 one end of which is disposed against the wadding 33 at the closed end of the shell casing. A washer 34 of resilient material, such as felt, is secured on the other end of the carrier, and a weight 35 in the form of a circular washer or disc of metal is disposed at the side of washer 34 remote from carrier 32 and secured to the carrier.

The carrier 32 is fomed from a sheet metal blank, as is particularly illustated in Figure 8, which has enlarged end portions 36 and 37 of substantially rectangular shape joined together by a strip 38 of a width materially less than the width of the end portions and having its longitudinal center line continuous with the longitudinal center lines of the end portions. A circular enlargement 39 is provided concentric with the mid-length location of the center line of strip 38 and is provided with a central aperture 40. The end portions 36 and 37 are formed to substantially semicylindrical shape and the strip 38 is bent at right angles at each side of the formation 39, bringing the semicylindrical end portions together to provide a cylinder, the outside diameter of which is less than the inside diameter of the shell casing 31. The formation 39 is now disposed substantially perpendicular to the longitudinal center line of cylinder 42 formed by the end portions 36 and 37 with the longitudinal center line of the cylinder passing concentrically through the aperture 40 and the length of the portions of strip 38 between formation 39 and end portions 36 and 37 is such that the side of formation 39 remote from cylinder 42 is substantially flush with or disposed within the open end of shell casing 31 when the end of cylinder 42 remote from formation 39 is against the wadding 33 at the closed end of the shell casing.

The diameter of formation 39 is also somewhat smaller than the inside diameter of the shell casing and the cleaning washer 34 is disposed within the open end of the shell casing at the outer side of formation 39 and has a diameter such that it is somewhat compressed in the shell casing and will expand in a gun barrel bore which the shell fits, so that it will guide the core member through the bore and also perform a cleaning action on the inner surface of the gun barrel.

The weight 35 is disposed at the side of the washer 34 remote from the washer adjacent end of the carrier and the weight, the washer and the carrier are secured together by a rivet 43 extending through central apertures 40, 45 and 47 in the carrier formation 39, the washer 34 and the weight 35 respectively.

The end portions 36 and 37 of the blank which end portions form the cylinder 42 are provided with apertures 49 which are punched out of the sheet metal of the blank in a manner to provide outwardly projecting points, as indicated at 50 in Figure 9, and a cylindrical body 53 of felt or other suitable bore cleaning material, surrounds the cylinder 42 and is secured thereto by the points 50 and by other means, if desired, such as by being cemented to the cylinder. This body 53 has a diameter such that it is slightly compressed in the shell 4 casing 31 and will expand in the bore of a gun barrel through which it is forced by discharge of the shell.

A powder charge 54 is provided in the shell between the end formation 39 of the core element and the wadding 33 at the closed end of the shell and a primer or cap 55 is inserted in the closed end of the shell in position to fire the powder charge.

With the cleaning shell located in the shell chamber of a gun barrel, when the powder charge in the shell is fired, it will drive the assembly including the carrier 32, the body 53, the guide washer 34 and the weight 35 through the bore of the gun barrel and the washer and the cylindrical body of cleaning material will thoroughly scrub the inner surface of the gun barrel and remove all foreign material, such as rust and burned powder therefrom.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is, therefore, to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claim rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claim are, therefore, intended to be embraced therein.

What is claimed is:

A bore cleaning shell comprising a hollow shell casing having an open end and a closed end, a primer extending through the closed end of the casing, a carrier disposed in the casing and including a cylindrical portion disposed adjacent the closed end of the casing and a disc shaped portion disposed within and adjacent the open end of the casing, a cylindrical body of cleaning material mounted on the cylindrical portion of the carrier and disposed within the casing adajcent the closed end of the latter, a disc of resilient material disposed against the side of the disc shaped portion of the carrier remote from the cylindrical portion of the latter, a weight dis posed against the side of the disc of resilient material remote from the disc shaped portion of the carrier, a fastener securing the weight, the disc of resilient material and disc shaped portion of the carrier together, and a powder charge disposed within said casing and extending through the cylindrical portion of the carrier to said primer.

References Cited in the file of this patent UNITED STATES PATENTS Feagin May 20, 1924 Symes July 14, 1936 l6,841 Great Britain of 1887

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