US3092026A - Shot load - Google Patents

Description

June 1 c. o. WILLIAMS ETAL 3,092,026

sHoT LOAD Filed Sept. 18, 1962 5 sheets-shat 1 INVENTORS CHARLES o. WILLIAMS 2 Z BY CHARLES E TURNER June 4, 1963 c. o. WILLIAMS ETAL 3,092,026

SHOT LOAD Filed Sept. 18, 1962 3 Sheets-Sheet 2 INVENTORS CHARLES 0. WILLIAMS CHARLES E TURNER A TIORNEY June 1963 c. o. WILLIAMS ETAL 3,092,026

snow LOAD Filed Sept. 18, 1962 5 Sheets-Sheet 5 FIG-5 INVENTORS CHARLES 0. WILLIAMS BY CHARLES F. TURNER A 7' TORNEV United States Patent 3,092,026 SHOT LOAD Charles 0. Williams, Hamden, and Charles F. Turner, Mount Carmel, Comm, assignors to Olin Mathieson Chemical Corporation, a corporation of Virginia Filed Sept. 18, 1962, Ser. No. 224,378 8 Claims. (Cl. IMP-42) This invention relates generally to ammunition and more particularly to an improved shotshell especially of a type containing buckshot.

.Shotshells containing large sized shot known to the trade as buckshot are provided for killing fairly large game and for use by peace officers in riot guns. Large shot such as No. 2 shot (0.15 of an inch in diameter), BB and buck ranges in size from a diameter of about 0.15 of an inch up to about 0.33 of an inch or greater and, consequently, only a relatively small number of these relatively large pellets can be loaded and are available in the conventional shotshell cartridge. In order for these shells to be effective, it is necessary that each of the pellets making up the load follow an even more accurate flight to the target than a shell with more but smaller pellets. In other words before such shells can be extended for certain uses, it is essential that the pellets remain exceptionally close together until they strike the target. Shotshell loads heretofore available especially with large sized shot have not been too satisfactory because the pellets of each load become too widely separated in flight.

It is, therefore, an object of this invention to provide an improved shotshell containing an exceptionally effective load of shot. Another object of the invention is to provide a shotshell containing a projectile charge including a few large size shot but nevertheless having improved accuracy characteristics. A further object of the invention is to provide a shot cartridge and especially a buckshot cartridge having shot pellets in combination with auxiliary charge elements which, when fired, will serve to propel'only the few shot very accurately towards the target and which elements offer no interference to either the shot or the shooter so an effective number of the pellets will strike the tar-get unaccompanied by confetti or the like which might discomfort or distract the shooter.

Other objects will become apparent from the following description taken in connection with the accompanying drawing in which FIGURE 1 is an elevational and fully longitudinal sectional view of one embodiment of the shell of this invention;

FIGURE 2 is an elevational view partly in section showing another embodiment similar to that of FIG URE 1 but modified as shown in the sectional part;

FIGURE 3 is a transverse cross sectional view taken along line 3--3 of either FIGURE 1 or FIGURE 2;

FIGURE 4 is an enlarged view showing a typical string of twelve N0. 00 shot pellets after projection out of the gun barrel from a 12 gauge shot shell of this invention and taken by flash photography at a distance of about 12 feet from the gun muzzle; and

:FIGURE 5 for comparison shows a similar View of a typical string of the same number of No. 00- shot projected from a conventional 12 gauge shell.

In accordance with this invention, the foregoing objects are accomplished, generally speaking, by providing a shot load arranged as a column having a projectile charge of spherical metal pellets and a suitable shot column encircling sleeve of cushioning material together with a matrix of cushioning material filling the interstices between the pellets in the cartridge.

It has been found that, despite the large size of shot,

a high improvement both in target striking efiectiveness and in durability of the shell case results from a combination of such a sleeve, of a special composition, intervening in the case between the case and shot column, together with the cushioning matrix in the form of a powder, particularly as the size of shot increases in and with respect to the range from about 0.15 of an inch to about 0.33 of an inch.

The sleeve is an axially or otherwise longitudinally slit layer forming a pad about the column of shot, usually of soft lead, a hardened alloy of lead or of lead plated as with an alloy of copper or with copper to increase the hardness and durability of the shot. The sleeve is of a cushioning material capable of plastic deformation for absorbing the outer shot pellets partially and preferably capable of self lubrication, such as polyethylene. This layer is of such thickness and softness relative to both the tubular part of the cartridge case, and also the shot that most of the permanent indentation and scufling and abrading occurring during shell firing is taken up in the sleeve aided by the coaction of the powdered cushioning material sifted among the spherical metal pellets to form a matrix which distributes the shock of firing more uniformly, thereby minimizing the creation of high pressure points.

Cartridges having a gauge not smaller than about a 20 gauge shotgun shell and not larger than about a 10 gauge shell are contemplated, but a 12 gauge shell is usually preferred as most adaptable to charging with all of the shot sizes involved.

The cushioning material sifted between the spheres is in granular form and may be of any suitable material softer than the spheres. Examples of such cushioning materials include resinous material, either synthetic or natural, which has the required lightness and rigidity and which can be loaded to a suitable packing density, including cellulose derivatives such as, for example, cellulose acetate, cellulose propionate, cellulose butyrate or ethyl cellulose and the like, or acrylic resins, polystyrene, polyvinyl acetate, polyamides, rigid urethanes, and the rigid high density grades of polyethylene or the like, or a suitable cellular material such as, for example, ground wheat grains, corn meal, sawdust or the like. The granulation of the cushioning material must be such that it will fill the interstices between the shot substantially without leaving these interstices as voids. The cushioning material or filler is either sifted or packed in the interstices in any suitable form so that the particles remain distinct instead of formin a solid fragmentation-resistant slug such as would be obtained by mixing and molding a cohesive matrix about the shot. A frangible matrix, forming cushioning particles under the impact of firings will also be suitable.

The encircling cushioning and lubricating layer extends over the shot column length in a single thickness of strip which is preferably press-fitted when loaded in the shot shell case to assume the form of a C-shaped band and thereby preferably prestressed to impart a bias giving the band a tendency to uncurl, to open out of its substantially closed ring shape as soon as it is free of the constraint of the shotgun bore. The band is a layer, plastically deformable by shot indentation and formed from a strip of suitable synthetic plastic material of a sufficient length, thickness and pliancy for the purpose.

A layer of high pressure relatively soft, self-lubricating polyethylene or other similar olefinic polymer for the purpose is contemplated in the form of a band curled to a split-ring shape when constrained in combination with a shot shell case, especially of the type having an evanescent end closure and a self-sealing flanged wad as disclosed in United States Patent No. 2,5 82,125 and pref- 3 erably as disclosed in United States Patent No. 2,582,124.

A suitably soft grade of polyethylene or any equivalent deformable and unctuous, i.e. waxy, olefinic polymer or co-polymer is contemplated in a thickness of not less than about 0.010 of an inch, but not more than about the thickness of the thickest shell side Wall encountered, i.e., not more than about 0.030 to 0.040 of an inch. This forms a plastically indentable pad movable as a unit with the short and matrix powder; and, therefore, with the shot and granular matrix, the pad forms part of the projectile load until ejection from the shotgun muzzle. During passage of the projectile load, the outer shot becomes absorbed partially in the pad by not only plastically indenting the surrounding layer but also by extruding parts of it up between them as the acceleration is applied to the load in the bore. Exteriorly of the barrel, the powder, and the collar become free of each other, and fall behind to leave the shot free from them.

The plastic takes the form of a suitable length of a rectangular strip bent round and with its extremities in abutment in order to fit snugly within the standard cartridge cavity as a seamed collar, but having suflicient memory characteristics so as to tend gently to uncoil free from the shot column upon emergence from the muzzle. The extremities must not be joined. The length is not more than that of the shot column so as not to interfere with contiguity of the shot and the end closure.

Other suitable resinous materials are compounds of polyvinyl chloride, ethyl cellulose, cellulose acetate, polyethylene terephthalate and the like, preferably lubricated and if of a suitable grade for the purpose. At the aforenoted thickness, a collar of solid high pressure polyethylene of relatively low molecular weight having a Shore durometer hardness of from about 50 to about 75 and preferably around and not in excess of about 65, measured on the C scale, is contemplated to offer the necessary degree of deformability, lubricity, and curl-back without having undesired resilience.

The cartridge shown in FIGURE 1 represents a 12 gauge buckshot load having about 12 pellets of shot 2 about 0.33 inch in diameter. This size pellet is known to the trade as buckshot. The total weight of the pellets is about 488 grains. The pellets were cast from either soft lead or a lead-antimony alloy. The shot may be of any other large size available and the number of pellets enclosed may be varied accordingly. For example, 16 pellets of #1 buckshot having a pellet diameter of about 0.3 of an inch or 27 pellets of #4 buckshot having a pellet size of 0.25 of an inch may be used. The pellets 2 are enclosed in cartridge case 1 of paper (a suitable plastic such as linear high density polyethylene is also contemplated) and the spaces between the pellets are filled by sifting with a cushioning material 3 such as granular ethyl cellulose.

The granular shot matrix and shot are encircled in the sleeve 40 parted on one side. The cartridge also includes a filler wad 5, a propellant powder charge 6, a base wad 7, a primer 8, and a metal head 9 around the closed end or base of the case.

According to above noted US. Patent 2,582,124, the end closure 10 of the FIGURE 1 cartridge is formed of contiguous circular sectors between reentrant folded or pie-cut crimps 11, all integral with the case 1 folded in all around the shell at 12 to form an evanescent closure in combination with the flanged Wed 14.

The cartridge of FIGURE 2 has case 21 with a metal head 29, shot 22, the matrix of granular cushioning material 23, the cushioning shot sleeve 50 and is modified according to US. Patent 2,582,125 so that the flanged wad (not shown because it is like that of FIGURE 1) is combined with the closed end 30 formed by the rolledover tube portion 31 and the top wad 32.

FIGURE 3 shows how the case 21, the shot 22, the matrix 23, and sleeve 50, and slit 51 forming a parting on a side, are related in the various embodiments described and contemplated.

For best results the granules of cushioning material should not be too coarse, preferably a powder not larger than about 0.050 of an inch is employed as a filler about the large shot in the split plastic sleeve. In the specific examples described, a fine particulate filler of ethyl cellulose, the bulk of which was of a size at least about 0.010 of an inch, having been retained on a 100 mesh screen was sifted between the shot. In any event, the particles must be shaped to be mobile enough to flow readily so as to sift into place between the metal spheres without need for more than pouring and vibration, or moderate tamping and force feeding, if packing is employed to increase the amount of matrix powder between the shot pellets.

In a 12 gauge shell having 12 pellets of #00 buckshot, the granular ethyl cellulose was sifted in to a charge weight of about 25 grains. In a 12 gauge shell having 27 pellets of #4 buckshot, about 18.3 grains were sifted in.

The wads may be formed from paper or any other suitable material. A conventional rolled enclosure may be used with advantage; but with rolled portion 31, end wad 32 is preferably made frangible according to Patent No. 2,582,125 and treated with a water proofing material. Tubes 1 and 21 may be a convolutely wound paper tube, a plastic tube or a metal tube. If the plastic resin or metal forms the case, a base wad may not be required and the separate head 9 or 29 is optional.

The shot pellets, although large are of subcaliber size, i.e., one is not enough to extend across the cartridge case cavity. They may be of any suitable metal, including iron, but are usually of lead, or a lead alloy such as one containing a small amount of antimony.

Shot fired from cartridges of this invention are deformed less in the shell case and gun barrel and are more closely spaced when they strike the target than are shot from prior art cartridges.

As an example, '12 gauge cartridges, some containing 12 pellets of No. 00 buckshot, some containing 27 pellets of No. 4 buckshot, and some containing 130 pellets of No. 2 chilled shot (1 /2 ounches), all having a fine ethyl cellulose plastic powder sifted between the shot within a sleeve of relatively soft high pressure type of polyethylene, were each, on the average, found to produce a superior pattern in a 30 inch test circle spaced 40 yards from the muzzle of a shotgun having a full choke, as compared to similar shells lacking either or both of a shot encircling polyethylene collar, and the ethyl cellulose powder.

For example, in the shell of FIGURE 1, the improved No. 00 buckshot load produced average patterns of about 100%; the No. 4 buckshot attained about 96% on the average, and the No. 2 chilled shot raised the average pattern from about 77% to about 92%. A pattern of or better is attainable with the shot sizes contemplated.

In comparing the fairly round shot 60 of FIGURE 4 with the string of shot 70 of FIGURE 5 it should be observed that the shot travels from bottom to top in that direction with reference to the page, and that with the (load of this invention (FIGURE 4) there is marked reduction in projected shot pellet deformation, manifested in conventional shot (FIGURE 5) as the badly flattened areas 71, and that there is reduction of lateral spread in the improved projected shot of FIGURE 4 to give evidently a tighter pattern or higher pellet density on the target. As a result, there is attainable an improvement from the 64% to 80% pattern density now available in conventional loads of this type on the average up to as high as now available in the loads made according to this invention, all as observed at a range of 40 yards in the 30 inch diameter circle used to test shot patterns.

What is claimed is:

1. A shot cartridge comprising a case having a caliber of from about a 20 gauge shotshell to about a gauge shotshell and having a tubular shell wall defining a cavity, a primed cartridge head closing one end of said case, a propellant charge in said cavity adjacent said primer, and a closure mounted at the opposite end of said case and yieldable upon ignition of said charge, a projectile load of relatively large and substantially spherical shot, all of a diameter smaller than said caliber, said shot being arranged in a column in said cavity adjacent said closure for forcing said closure open and projection from said case and through the bore of a shotgun of said gauge in columnar arrangement, a charge obturating means including at least one wad snugly fitted with said case in said cavity between said charge and load, a band of resinous plastic cushioning material softer than said shot extending between said obturating means and yieldable closure and disposed between said column and shell wall to be constrained by said wall to curl said =band about said column in the form of a sleeve open at least at one end adjacent said closure and with a slit down the side, said slitted sleeve producing its own bias tending to uncurl said band tree from said shot upon emergence from said shotgun bore, and a matrix of relatively fine particles of non-metallic cushioning material substantially completely filling the portion of the sleeve not occupied by the shot, whereby the load is adapted to be projected from said bore free from said sleeve and particles toward a target with a pattern improved in comparison with the pattern obtainable in the absence of one of said particles and sleeve.

2. The cartridge of claim 1 wherein the load is buckshot and wherein all of the particles are mobile and have no dimension larger than about 0.050 of an inch.

3. A shot cartridge comprising a cantridge case, having a caliber of from about a 20 gauge shotshell to about a 10 gauge shotshell and a tubular shell wall defining a cavity, said case being provided at one end of said wall with a cartridge head carrying 'a primer, a propellent charge in said cavity adjacent said primer for charge ignition, said case being provided at the opposite end of said case with a cavity closure yieldable upon ignition of said charge, a projectile load of relatively large and substantially spherical shot all of about the same size smaller than said caliber and of a diameter within the range from about 0.15 of an inch to about 0.33 of an inch, said shot being arranged in a column in said cavity adjacent said closure for forcing said closure open and projection from said case and through the bore of a shotgun of said gauge in columnar arrangement, a charge obturating means consisting of at least one wad snugly fitted with said case in said cavity between said charge and load, a band of resinous plastic cushioning material softer than said shot extending between said obturating means and yieldable closure and disposed between said column and shell Wall to be constrained by said wall to curl about said column in the form of a sleeve open ended at least at said closure and with a longitudinal slit, said slitted sleeve producing its own bias tending to uncurl said band free from said ShOzt upon emergence from said shotgun bore, and a matrix of relatively fine particles of nonmetallic cushioning material substantially completely filling that portion of the sleeve not occupied by the shot, whereby the load is adapted to be projected from said bore free from said sleeve and particles toward a target with a high pattern density of at least 4. The cartridge of claim 3 wherein the band of resinous plastic cushioning material is a polyethylene.

5. The cartridge of claim 3 wherein the closure is a portion integral with the tubular shell wall folded across the opposite end of the case, the band upon projection being also constrained by the yielding closure, and the obtur-ating means includes a flanged wad next to the propellant charge.

6. The cartridge of claim 3 wherein the band of resinous plastic cushioning material is a polyolefin.

7. The cartridge of claim 3 wherein the particles are ethyl cellulose.

8. The cartridge of claim 3 wherein the particles are polyethylene of a rigid high density grade.

References Cited in the file of this patent UNITED STATES PATENTS 17,287 Lindner May 12, 1857 2,582,125 Holmes Jan. 8, 1952 2,897,758 Miller et al Aug. 4, 1959 FOREIGN PATENTS 6,184 Germany Jan. 19, 1879 416,520 Germany July 16, 1925 507,888 France July 8, 1920

Claims (1)

1. A SHOT CARTRIDGE COMPRISING A CASE HAVING A CALIBER OF FROM ABOUT A 20 GAUGE SHOTSHELL TO ABOUT A 10 GAUGE SHOTSHELL AND HAVING A TUBULAR SHELL WALL DEFINING A CAVITY, A PRIMED CARTRIDGE HEAD CLOSING ONE END OF SAID CASE, A PROPELLANT CHARGE IN SAID CAVITY ADJACENT SAID PRIMER, AND A CLOSURE MOUNTED AT THE OPPOSITE END OF SAID CASE AND YIELDABLE UPON IGNITION OF SAID CHARGE, A PROJECTILE LOAD OF RELATIVELY LARGE AND SUBSTANTIALLY SPHERICAL SHOT, ALL OF A DIAMETER SMALLER THAN SAID CALIBER, SAID SHOT BEING ARRANGED IN A COLUMN IN SAID CAVITY ADJACENT SAID CLOSURE FOR FORCING SAID CLOSURE OPEN AND PROJECTION FROM SAID CASE AND THROUGH THE BORE OF A SHOTGUN OF SAID GAUGE IN COLUMNAR ARRANGEMENT, A CHARGE OBTURATING MEANS INCLUDING AT LEAST ONE WAD SNUGLY FITTED WITH SAID CASE IN SAID CAVITY BETWEEN SAID CHARGE AND LOAD, A BAND OF RESINOUS PLASTIC CUSHIONING MATERIAL SOFTER THAN SAID SHOT EXTENDING BETWEEN SAID OBTURATING MEANS AND YIELDING CLOSURE AND DISPOSED BETWEEN SAID COLUMN AND SHELL WALL TO BE CONSTRAINED BY SAID WALL TO CURL SAID BAND ABOUT SAID COLUMN IN THE FORM OF A SLEEVE OPEN AT LEAST AT ONE END ADJACENT SAID CLOSURE AND WITH A SLIT DOWN THE SIDE, SAID SLITTED SLEEVE PRODUCING ITS OWN BIAS TENDING TO UNCURL SAID BAND FREE FROM SAID SHOT UPON EMERGENCE FROM SAID SHOTGUN BORE, AND MATRIX OF RELATIVELY FINE PARTICLES OF NON-METALLIC CUSHIONING MATERIAL SUBSTANTIALLY COMPLETELY FILLING THE PORTION OF THE SLEEVE NOT OCCUPIED BY THE SHOT, WHEREBY THE LOAD IS ADAPTED TO BE PROJECTED FROM SAID BORE FREE FROM SAID SLEEVE AND PARTICLES TOWARD A TARGET WITH A PATTERN IMPROVED IN COMPARISON WITH THE PATTERN OBTAINABLE IN THE ABSENCE OF ONE OF SAID PARTICLES AND SLEEVE.

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