US2582125A - Ammunition - Google Patents

Description

Jan. s, 1952 R, Q HOLMES 2,582,125

-\ AMMUNITION Filed Sept. v29, 1947 'lill/111111111111111 III/II @9090@ ad 'e INVENTORC i ff; La?, 9" RAYMOND' S. HOLMES ATTORNEYS.

' @eluted .ian- 8, 1952 AMMUNITION Raymond s. Holme., Alton, nl., assigner t oun Industries, Inc., East Alton, Ill., a corporation of Delaware Application September 29, 1947, Serial No. 776,837

12 Claims.

This invention relates generally to shot cartridges and particularly to shot cartridges of the type in which there is a positive seal between the combustion gases and the shot charge. This application is a continuation-impart of my prior copending application, Serial No. 616,526, filed September l5, 1945.

Numerous workers in the prior art have believed that the performance of shot shells would be improved by the provision of wadding of such character that a substantially hermetic seal would exist between the shot charge and the propellent charge thus to positively conne the powder gases behind the shot charge, both in the shell itself and in the gun barrel, and many proposals in this direction have been made. Experience demonstrated, however, that the rounds provided with the supposedly improved seal behaved in an undesirable manner, yielding patterns which were erratic and less suitable than the products which they were intended to supersede.

These experiences with substantially hermetic wadding led to the belief that some leakage of powder gas past the wadding was not only desirable but necessary to secure uniformity of patterns from round to round and satisfactory distribution of pellets in the pattern of the individual rounds. In my copending application, Serial No. 616,526, I pointed out that such gas leakage was not necessary in the case of shot shells which were free of top (over-shot) wads. In fact, test data included in said application show that, absent an end closure of such character as to obstruct the movement of the shot pellets through space, an hermetically sealing gun wad (between the propellent charge and the shot harge) does, in fact (contrary to previous experience), result in improved patterns and other desirable features. Subsequent observations not only confirm the aforesaid discovery. but extend it beyond shells with integral top closures (,as shown in said application) to shells whose ends are closed by means of wads which offer no substantial retardation to the travel of the shot pellets through space.

While it has heretofore been proposed, as in United States Patent No. 929.866, to eliminate the top wad and close the end of the shot shell tube by deformation and infolding of the side walls of the tube, and indeed substantial quantities of shot shells have been manufactured with the ends so closed, the lesson learned by the art with respect to the necessity of gas leakage has continued to prevail so that those shells whose end closures have been integral with the 2 side walls of the tube have heretofore been provided with wadding between the shot charge and the propellent charge, which admitted of some gas leakage.

It is evident, of course, that such gas leakage represents a loss of propellent power and that the heat of the combustion gases in contact. with the shot charge contributes to the tendency of the shot pellets to weld together, as well as to their tendency to foul the gun bore.

In the aforesaid application, the substantially hermetic wadding between the propellent and the shot consisted of a flanged disc wherein the flanges were smooth and extended in the direction of the propellent, snugly engaging the interior of the shell tube. While such wads' were eminently satisfactory from the performance standpoint, some diiculty was encountered in loading such shells by automatic machinery in that the Wad was driven home so rapidly as to build up substantial air pressures behind it. In some cases (which were rare but nonetheless too prevalent for the highest quality ammunition), the pressure of the thus entrapped air reached a magnitude sufcient to displace-cock-the wad when the mechanical force thereon was released. Quite naturally, the ballistic results obtainable from such a shell were at variance with the desiderata.

'Ihe object of the invention, generally stated, is to provide a shot shell in which leakage of gas past the wadding is minimized without the disadvantageous effects above described.

Another object of the invention is to provide a shot cartridge of the type described, in which is incorporated a gun wad of such form and dimensions as to furnish an optimum gas seal with the gun barrel without adversely aiecting the pattern.

Another object is to provide a gun wad which will furnish an eifective gas seal and also be capable of withstanding the firing pressure without disintegrating.

Further objects will appear from the detail description taken in connection with the accompanying drawings, in which:

Figure 1 is a longitudinal sectional view of a shot cartridge embodying the invention;

Figure 2 is a perspective view of a gun wad usable in the shell shown in Figure 1;

Figure 3 is a view corresponding to Figure 2, but showing another form of gun wad wherein the flanges are fluted;

Figure 4 is a sectional view of another embodiment of a shot cartridge embodying the present invention; and

Figure is a perspective view of a breakable wad utilized in effecting the endl closure of the shell shown in Figure 1.

According to the present invention. a shot shell. provided with a substantially self-sealing wad between the shot charge and the propellent charge, has its end closed to connue the charges by an evaneseent closure.. By evanesoent ciosure, as used herein.,is meant a closure which will confine the shot within the shell during ordinary handling, but which. when the shell is red. has the capacity of substantially freeing itself from the trajectory of the shot pellets. so that there are no solid parts of a character such as to obstruct the movement of the shot pellets through space. Buch escape from .the trajectory may be either real (as in the ease of tube-integral closures) or effective (as in the case of disintegrating top wads) provided that, at and beyond the murale of the gun. the end closure does not exist in a form which will deflect or impede the travel of the shot pellets through space. Accordingly. such an evaneseent closure may, for example, be of the form disclosed generally by United States Patent No. 920,860 wherein the end of the tube is creased and infoided to form the closure and, upon firing, such end closure remains integral with the shell. Alternatively,

' the evaneseent closure may involve the use of K plates the combination of an evanescent closure for the shot shell tube with a self-sealing gun wad of the character of a hanged disc arranged with the flanges to trail the web of the wad upon firing, i. e., with the flanges directed toward the base of the loaded shell. Such a flanged disc may be formed of consolidated fibrous sheet material, such as paper. Shells embodying selfsealing gun vvadsl of this type with a shot shell tube having an evanescent closure not only exhibit uniformity of pattern and elimination of lead deposit in the gun bore. but also exhibit a unique uniformity of report. marked reduction in confettiing. and considerable reduction of powder residue in the gun barrel. l

The present invention further contemplates the provision in the flanges of the gun wad aforesaid of a sucession of axially extending flutes. These may be formed concurrently with the fianging of the disc by the utilization of uted male and female forming dies.

Referring now to Figure 1 of the drawings for anillustrative embodiment of the invention, the shell consists of a suitable base i and the usual paper tube 2. A primer assembly l is mounted in the base l, and thereabove within the tube 2 is a propellent charge 4.

Inthe embodimentshowninlligure Lagun wad l of the character shown in detail in Figure 2 is provided immediately overlying the propellent I, and confining the latter. The gun wad I consists of a iianged disc of consolidated nmentioned, for example 0% of the diameter, efficient gas seal is not obtainable. Increasing the depth of the nange beyond about onethird the. diameter increases the manufacturing diilicuities. without contributing any advantageous results. Excellent gun wads for use in lz-gauge shot cartridges have been obtained by iianging circular discs of paper 0.035" in thickness, ranging from 0.875" to 1.20" in diameter, using cupping die having a male member (defining the interior diameter, between the ilanges of the wad), 0.720" in diameter.

It has further been found that gun wads which are not subject to undesirable disintegration and delamination when fired in a gun are obtainable by the use of heavily calendered paperboard. Impwsmition of the cardboard with a high melting point wax composition is desirable, though not essential. While a variety of wax compositions, having melting point higher than about C., has been found effective for the purpose, without adversely affecting the propellent powder charge. particularly good results have been obtained with the use of microcrystalline waxes of petroleum origin. such as "Socony 2300" and "Moore and Hunger 3300". For example, wads of cardboard were thoroughly impregnated with about 25% of their weight of wax by ten minutes submersion in molten wax at C. followed by ten minutes of centrifuging at 30 C.

In the embodiment shown, a succession of filler wads, including a card wad 1 and two molded wads I of conventional form, are inserted above the gun wad I. Therebeyond, the shot charge l is placed in the tube 2, and finally the end of the tube 2 is closed to confine the shot charge, the wadding. and propellent, by the provision in the illustrated embodiment of a disintegratins t0n wad Il, held in place by inturning and crimping theendoftube2,asshownat li.

While the wad Il may be formed of any suitable composition known in the art for the production oi a frangible, disintegrating, or breakable top wad, good results have been achieved with wads which are cut from any of a great'variety of chipboard, about 0.025" thick. After cutting the discs from the paperboard sheets. the discs are immersed in a sodium silicate solution having a specific gravity of 1.1 for approximately thirty minutes. Thereafter the discs are removed and drained of excess sodium silicate solution. The discs are then dried with circulating hot air at a temperature of C. for two hours. During the dryln! cycle, the discs are continuously tumbled to prevent sticking together. Thereafter the discs are aged for a period of about two days. to allow the sodium silicate to fully set before the wads are applied to shot shell tubes.

Anotherembodiment is shown in Figures,

brous sheet material such as paper. Alterna- 1s wherein the components are identical with those shown in Figure 1, save thatl in'the embodiment of Figure 4, the evanescent closure is accomplished by creasing the tube Iv near its mouth at. for example, six equidistant places. and then infolding the creased portion to provide a closure i2 integral with the tube 2, in the manner generally comparabley to that disclosed in United States Patent No. 929,866. The tube-integral closure utilized in this embodiment results in a somewhat shorter shell than that shown in Figure l, when tubes of the same original length are utilized. In order to accommodate the same propellent and shot charges in the two shells, however. the difference in dimension is made up by changing the thickness of the wadding which separates the propellent from the shot charge. Consequently, in the embodiment shown in Figure 4, the filler wads 8 of the previous embodiment are replaced by a single filler wad It of the same type, but oi larger axial dimension than the combined axial dimension of the two iiller wads 8 in the previous embodiment.

Comparative tests among a series of shells, with and without self-sealing gun wads of the character above described, and with and without the evanescent end closure of the shot shell tube. demonstrate the great superiority patternwise of the self-sealing gun wad with evanescent end In another test, using 12-gauge traploads, an additional nine-series of forty rounds each were red, with the following pattern results:

Pattern-Percentage of flelxlatsdlsn 30" Circle at ar Series Top Closure oveggdwder Average mRomds Max. Min

l Fi .l Conventional. 62 74 60 11 Fig. 4 do 60 76 48 l2 Conventional. do 58 73 4l 13 Fig. 1... Fig. 2- 68 74 55 li Fig.4 do 69 76 59 l Conwntionnl. d0 59 72 43 16 Fig. 1 Fig.3 70 76 63 17 Fig.4..... do 68 73 59 18 Conventional. do 59 72 4l The conventional over-powder wadding in series 1, 3, 10, and 12, and series 2 and 11, were identical with that shown inFigure 1 and Figure 4, respectively, save that the gun wad l or IB was replaced by a. duplicate of the card wad 1. The conventional" top closure in series 3, 6, 9, 12, 15, and 18 was identical with that shown in Figure l, save that the breakable top wad I0 was replaced by a card wad of the same size and shape. All other components of the shells involved in the several series of game-load tests were identical.

Likewise. all other ents o! the shells iiivoived in the several series of trapload teste were identical. The trapload differed trom the gameu load in propellent charge, shot charge. and base 5 structure (the latter being as specifically shown in the parent application Serial No. 616,528) in the usual manner.

From the foregoing test results, it is apparent that with a conventional end closure, the use of either style (Figure 2 or Figure 3) of self-sealing gun wad was productive of pattern results in some cases worse, and in no case substantially better, than with conventional over-powder wadding. On the contrary, with the evanescent end closures (of either the Figure 1 or Figure 4 type) the average patterns are considerably better with the self-sealing gun wad than with the conventional over-powder wedding. While the breakable top wad type of end closure appeared in all combinations to yield patterns somewhat better than the conventional top closure, the improvement was particularly striking in the combination with the self-sealing gun wad (of either style). In the latter case, while the average pattern is only one or two percentage points better when, with conventional over-powder wadding, the tube-integral end closure. rather than the conventional end closure, is employed (compare series 2 vs. 3, 11, vs. 12); where the self- 30 sealing gun wad is used, the dinerence becomes thirteen (series 5 vs. 6), twelve (series 8 vs. 9), ten (series 14 vs. l5), and nine (series 17 vs. 18) percentage points. Moreover, the patterns resulting from shells where in either the overpowder wedding or the end closure was conventional, were consistently more erratic (see minimum column) than those resulting from shells having either type of evanescent closure, with either type of cupped wad. This clearly demonstrates a peculiar cooperative action between the cupped over-powder wad and the evanescent end closure.

Additionally, the tested shells which were provided with both an evanescent end closure and the cupped gun wad were characterized by a greater uniformity of report than the tested shells which omitted either or both of these features. These improvements in pattern and report are accomplished without sacrifice of muzzle velocity or velocity over a range of forty yards. Indeed, in most instances the muzzle velocity and the average velocity over forty yards was increased above the values obtainable where the same propellant/'and shot charges were used with conventional components.

From the foregoing description, it is apparent that the invention accomplishes its objects, and provides a substantially improved shot shell. While the invention is not limited to shot shells o provided with components as speclilcally shown in the drawings, it is evident that the improved results are accomplished by the combination of an evanescent top closure and a self-sealing gun wad. The other components of the shell may be g5 varied at will to t the conditions for which the load is intended, in accordance with the usual practice in the ammunition art, and without departing from the spirit of the invention or the scope of the appended claims.

.Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

J l. A shot shell having a tube, a propellent charge and a loose shot charge within the tube, 7s a hanged disc wad between the propellent charge #saam and the shot charge, and an evanescent closure l for the tube contiguous `with the shot charge.

.2."A shot shell having a tube. a proponent charge and a, shot charge within the tube, a nangedisc-wed between the propelient charge and the shot' charge. and an evanescent closure for the tube comprising a frangible wad.

8.,A shot cartridge having a shell. a charge ofA propellent powder. therein, a gun wad consisting oi a ilanged disc o!` consolidated iibrous material pressed into contact `with and enclosing the upper portion of the said powder charge, a shot charge above the said vlad, and an evanescent 'closure for the'shell contiguous with the'shot charge. f

`4L1Af`shot cartridge lhaving a shell, a charge of propellent -powder therein. a gun wad consisting of a flanged disc o! consolidated tibi-ous material pressedinto contact with and enclosy ing the upper 'portion ofthe said powder charge.v

a shot charge above the said wad, and an evanescent closure for the .shellcomprising a trangible wad. Y s

' 5. A shot cartridge having a shell. a charge of propelle'nt powder,therein,.a.gun wad consisting oi a ilanged disc of iibrous material pressedinto contact, with and enclosing the upper portion of the said V powder charge, vsaid wad being impregnatedwith a high meltingpoint wax, a shot charge above the said wad, and. an evanescent closure for the shell comprising'a Vfrangible wad.

46. A' shot cartridge having a shell. a charge ot propellent powder therein, a gun wad consisting of a flanged disc o( fibrous material pressed into contact with and enclosing the upper portion of the. said powder charge, said wad being impregnatedwith av microcrystalline wax, a shot charge above the said wad, andan evanescent closure Vfor the shell contiguous with the shot charge.'

- '7 1 A shot cartridge having a shell, a charge of propell'ent powder therein, a gun wad consisting of aiianged disc enclosing the upper portion of the said powder charge, the length of the danses of the disc vbeing substantially one-tenth to onethird the diameter of the disc, a loose shot charge la'lzaove thev said, wad.,lv and `an evanescent closure for the'shell contiguous vwith the shot charge.'

8. A shot' cartridge having a shell, acharge of propellent powder therein, a gun wad consisting of a' ilangeddisc bssedfintoscontact with and.

enclo'sihgftheupper pprtionoi the said powder charge, the depth of thesaidnanged disc beinir 8 substantially one-tenth its diameter, @loose shot charge abovethe said wad, and an evanescent closure for the shall contiguous with the shot charge. i,

9. A shot cartridge having a shell. a charge of propellent powder therein. a gun wad consisting of a dangeddisc pressed into contact with and enclosing the 'upper portion oi the said powder charge, atleast one resilient wad and a loose shotcharge super-posed on the said iianged'disc,

` and an evanescent closure tor the shell contiguous with the shot charge. v

l0. Ashot cartridge lhailing a shell, a charge ot.propellent therein, a gun wad consisting oi a hanged disc ot pressure-resistant material overfthe said powder charge. a loose shot charge above the said wad, andan evansscent.

closure for the shell contiguous with the shot charge..

11. A 'shot shell'having avtube, a propellent charge and a loose shot eharge'within the tube, a flanged disc wad between the propellent charge and the shot charge, said wad being pressed into contact with the propclient charge to confine the same, andan evanescent'closure for the tube contiguous4 with the shot charge.

12.A shot shell having a a propellant charge and a loose shot charge within the tube, a substantially self-sealing gun wad between the propellent charge and the shot charge, and an evanescent closure for the tube contiguous with the shot charge.

, RAYMOND S. HOLMES.

REFERENCES CITED The following references are ot record in the file of this patent:

UNITED s'ra'rss rsm'rs

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