US1972996A - Shot shell and process of making same - Google Patents

Description

Sept. 11, 1934. E, J JOHNSON 1,972,996

SHOT SHELL AND PROCESS OF MAKING SAME Filed July 18, 1931 s Sheets-Sheet 1 FIG. 5

' FIGA:

I I W cf. (15 hnsow,

J M TTTT Sept. 11, 1934. E. .1. JOHNSON SHOT SHELL AND PROCESS OF MAKING SAME Filed July 18, 1951 5 Sheets-Sheet 2 mm m Mai WW m J H Edwvw Sept. 11, 1934. E J OHNSON 1,972,996

SHOT SHELL AND PROCESS OF MAKING SAME Filed July 18, 1931 5 Sheets-Sheet 3 Big. 6.

glwventcw JJolo/nson gig I Patented Sept. 11, 1934 PATENT 1 OFFICE 1,9723 SHOT SHEIL'AND PROCESS 'OF MAKING SAME- Edwin J. Johnson,

alsignor to" Montreal, Canadian In Quebec, Canada,

dosh-lea Limited Montreal, Quebec, Canada, a corporation of Canada Application July 18, 1931, Serial No. 551,779

27 Claims.

This invention relates to shot shells and processes of making same, and it comprises a waterproofed shot-shell, having a paper tube body impregnated to the outer surface with a waxy material, such as parafiin, ceresin, ozokerite and the like, the surface of said paper body being uniformly and substantially free from a film of unabsorbed wax and provided with a hard, dry, cohesive sheath produced from an applied pyroxylin composition; and it further comprises a process of producing such a waterproofed paper shot shell by impregnating said paper tube with wax, removing sup'erficial wax by mechanical action to produce a uniform surface free from a film of unabsorbed wax and applying to said film-free surface a pyroxylin composition and allowing the sameto dry and harden; all as more fully hereinafter set forth and as claimed.

This application contains subject matter commonto applicants prior co-pending applications Serial Nos. 92,594 and 264,967 of which applications the present case is a continuation in part.

The main object achieved in the present invention is the manufacture of shot shells which are thoroughly moisture proof and are unaffected by atmospheric conditions, which can be fired in rapid succession from a gun without tending to stick in the hot barrel, which'do not tend to stick in the breech, which are strong, durable and sufliciently rigid to withstand the rough usage to which shot shells are usually subjected in and' out of the gun, and which are at the same time sufficiently elastic to allow for the necessary degree of expansion upon firing without liability to rupture.

Shot shell tubes are usually made of cardboard or heavy paper; often without any particular treatment. It is recognized that absorption of moisture by these tubes creates difliculties of. various kinds; and particularly swelling. With the accurate mechanism of a good gun the permissible variation in size is very little. Any substantial absorption of moisture and swelling may render it diflicult or impossible to handle a shell by the gun mechanisn1 Various ways of waterproofing shells and protecting them against rain, snow and atmospheric conditions have been proposed, but not found satisfactory in practice; largely because of other difiiculties arising. A shot she 1 tube must be quite rigid and yet have a certain degree of elasticity to fulfill the requirements of firing in magazine guns. It is not permissible to use any, waterproofing composition materially affectingthese properties.

In brief, my process of waterproofing shot shells comprises impregnating a paper shot shell tube heating section, heat being supplied by the coils with wax, removing the film of superficial wax atelevated temperatures by mechanical action, (including within this term removal by chemical action and by rubbing. brushing, wiping, i solving, tumbling and absorbing operations) and finally applying to the film-free surface so produced a pyroxylin lacquer of special composition. In order to exemplify my process, a specific example of' its application will be described.

In the production of waterproofed shot-shells several pieces of mechanical equipment are useful. These will be briefly described in connection with the accompanying drawings. In this showmg:

Fig. 1 is a front elevation of a rotary drier or wax removing device with rotating shaft and heating coils shown in dotted lines.

Fig. 2 is a longitudinal section through the wax removing device along the line 2--2 of Fig. 3, parts being shown in elevation.

Fig 3 is a plan view, a section being taken along the line 3-3 of Fig. 2 to show the construction of the rotary shaft.

Fig. 4 is an end view of a sawdust rumbler, shown in elevation.

Fig. 5 is a front elevation of the rmnbler.

Fig. 6 is a side elevation of a dipping or coating machine.

7 is a plan view of the coating machine, while I Figs. 8 and 9 show details of a shot-shell rack for holding shells in the coating machine during operation.

In the figures like numerals refer to like structures. Figs. 1, 2 and 3 show details of a structure suitable for removing superficial wax from paramn impregnated shot-shell paper tubes. The structure of this wax removing device is essentially that of a rotary drier. A hopper 1 is employed for introducing the paper tubes, usually cut to shot-shell length, into the rotating shaft 2, of the device. This shaft 2 runs through two chambers, 11 and 17. The first chamber 11 is a of pipe 12 and 13 which surround the rotating shaft on all sides. The rotary shaft of the drier is perforated in four series of holes, 3, 4, 5 and'fi which allow any'melted wax to drip into the receiving pans 14. Access to these pans is provided by the hinged doors 15 shown in Fig. 1.

In chamber 17 of the wax removing device the paper shot-shell tubes are subjected-to treatment with air which blows against them at a high velocity. Air is blown into the lower end of the rotary shaft 2 by means of the fan 19. This fan 19 may be driven by abelt (not shown) operating on the pulley which is mounted ona base adhering to the paper tubes.

After passing through,the rotary shaft 2 the paper shot shell tubes are discharged from a trap door, not shown, at the lower end of the shaft and into the discharge spout 32. The trap door is opened once during every revolution of the shaft 2, being closed thereafter to prevent'the escape of the heated air inside the shaft. The paper tubes are caught in a barrel which is placed beneath the spout 32.

The rotating shaft 2 of the wax'removing device is provided with a spiral baflie or-a worm 16, the structure of,which is shown best in Fig. 3. This worm serves to propel the paper tubes through the rotary shaft.

After the removal of the superficial wax in the wax removing device, the paper tubes are intro-- duced into a rumbler shown in Figs. 4 and 5. This rumbler may consist of an octagonal shaped drum 26 mounted on a shaft 8 and driven by a belt 34. A hand-wheel 31 is provided at the other end of shaft 8. Sawdust and paper tubes are introduced into the drum 26 through a trap door, not shown.

After rumbling is completed the trap door is opened and the mixture of sawdust and tubes is dicharged into the lower part of the device; The

around the sprockets 44, 40, 45, 46 and 4'7. A

dipping well 39 is provided below the sprocket'40. This well is filled with a suitable lacquer composition which is kept at a constant level by means' of the overflow 48. Fresh lacquer is continually pumped from the reservoir 49 and through the pump 50 into the well 39. Upon overflowing, it returns to the reservoir 49. A float 51 is provided in thereservoir to serve as a warning when'the supply of lacquer becomes depleted. The sprocket chains 355 -35 are driven by means of the motor 3, the reduction gearing 37 and the chain 38, while the pump is driven by the chain 53.

In order to point out more specifically the details of my process I will now describe the manufacture of waterproof shot-shells in more detail, the description including the operation of the various devices described above.

The first step in the process of making the paper tubes for shot-shells comprises rolling the paper into'the form of tubes on a mandrel. The paper is coated on both sides with a paste as it passes through a pasting machine prior to rolling. In this process the composition of the paste is important. Not more than one part of wax to 128 parts of starch should be employed. A simple composition for this paste is as follows:

Starch 2 pounds Japan wax ounce Water 10 quarts Upon boiling, the above composition forms a thick paste which coats the paper with a gelatinous layer. This dries to a strong, hard flexible coatthat is diflicult to remove and which passes the sizing operation without rupture. After pasting and rolling, the tubes are dried and seasoned in a damp atmosphere before sizing. The sizing operation is carried out in a machine which automatically puts the tubes on a mandrel and pushes both tubes and mandrel through the die so that the resulting tubes have a definite diameter falling between certain prescribed limits. This diameter amounts to 0.787 inch for 12 gauge tubes, for example.

The wax employed in the paste is required as a lubricant during the sizing operation. If a small proportion is not used the paper tubes usually crumple up on the mandrel and are rendered useless. The size of the die' through which the paper tubes are pressed determines whether the sizing is hard or "soft. Hard sized tubes have a high gloss on their surface, while soft sized tubes have a dull surface appearance. The hardness of the sizing determines to a large extent the rapidity of wax absorption during a laterstep of the process.

After sizing, the tubes are cut in an automatic machine into short cylinders of a length suitable for assembly into the shot-shell. A 12 gauge shell, for example, requires a paper tube with a length, when cut, of 2% inches. After cutting approximately to length the paper tubes are ready for impregnation with wax.

Various of wax may be employed, such as ceresin and ozokerite, but I have found that a highgrade parafiin wax having a melting point lying between 123 to 126 F. and having a low oil content is advantageous. The wax is placed in a tank, melted and raised to a temperature of 180 to 190 F. before the paper tubes are dipped. The paper tubes are placed in a wire basket and immersed for from one to two hours in the bath of molten wax, depending on the rate of wax absorption. The bath of wax may be thermostated in order to maintain a constant temperature and a uniform product:

-It has been found that the paper tubes prepared as described tend to absorb w'axlongitudithe practice to allow thepaper tubes to remain in a bath of wax for a short time after they had become completely saturated. In this case, even after subsequent heating and draining treatments to remove wax, the wax content was still from 20 to 25 per cent of the total weight of the waxed tube. In mypresent process, however, the paper tubes are advantageously withdrawn from the moval and rumbling operations.

barrel of this hot sawdust is introduced-to I In the wax impregnation process the temperature of the bath is important. If the temperature falls much below 130 F. the rate of absorption is low and a larger proportion of waxds obtained in the finished tubes, while, if the bath rises much above 190 F'., there may ensue an objectionable cooking or baking of the paste which is present between the layers of paper. The paste tends to lose its adhesive'ness. It is obvious, of course, that the temperature of the bath must be kept well below the point at which the paper tends tochar. The tubes impregnated at a low temperature tend to exude wax even after'the final treatment for wax removal.

It is important to maintain the paper tubessomewhat under-saturated for best results. It is also advantageous to cut the tubes to cartridge length before the wax impregnation. As mentioned previously the wax is mostly absorbed longitudinally from the ends of, the tubes. If the tubes are long they tend to .become under-saturated at the center and super-saturated at the ends. Uniformity of impregnation is thus difiicult. A considerable saving of time also results from the cutting of the tubes; This cutting to length prior to impregnation with wax constitutes an important step in my new process.

Of course the cutting of the paper tubes to shot shell length prior to impregnation with wax and the withdrawal of .the tubes from the impregnating bath prior to complete, saturation are manufacturing refinements which are 'not essential to the production of satisfactory shot-shells. As described in my copending application. Serial No. 264,967, filed March 26. 1928, impregnation with parafiin may be by dipping, coating, spraying and the like. But it is preferable to use only about 18 per cent'by weight of the paraflin in the the paper containers.

After the tubes are impregnated with wax, they are dumped into the hopper of the wax removing device shown in Figs. 1, 2 and 3, described previously. The rotation of the shaft 2 of this device is controlled to 3 to 4 revolutions per minute. The shaft of the device is tilted at an angle 1 of 2 or 3 degrees to the horizontal to facil'tate the passage of the tubes through the chambers 11 and 17. The length of the shaft is about 15' feet and the paper tubes are conveyed through it and ejected in about 12 minutes. The temperature of the heating section 11 is maintained at about 220 to 240 F. while the air blowing through chamber 17 is maintained at about the same temperature. This air is circulated over the paper tubes in the latter chamber at the rate of about 250 cubic feet a minute. It may be said that this air exerts a wiping action on the tubes.

When discharged from the wax removing device, the paper tubes have the appearance of being free from superficial Wax. However. they sometimes still possess a film of wax over the surface, the surface layers showing a higher wax content than the inner layers. It'is necessary to remove this wax film in order to successfullylacquer the paper tubes. This film of wax may be sufficiently removed by rumbling in sawdust, for example.

The rumbling operation is conducted in the device shown in Figs. 4 and 5, described previously. The rumbler is rotated at approximately 24 revolutions per minute and from 15 to 20 minutes. The sawdust used in this rumblingoperation is heated to a temperature of. from 180 to 190 F. by means of an auxiliary oven, not shown. prior tointroduction into the rumbler. About 1 barrel of paper tubes. Soft wood sawdust is employed, which may be screened to remove coarse chips as well as fine 'dust. When fresh,

the sawdust must be dried to reduce its mois-v ture content .to from 4..to-8 per cent. The sawdust can be re-used several times in the rumbling operation, being reheated between each operation. When the wax content of the sawdust reaches a maximum of about 8 per cent of wax it should be discarded. The actual amount of wax removed in the rumbling operation is small, amounting to only about 0.03 weight of the tubes treated.

The rumbling operation consists essentially in a mechanical removal of the surface film of wax. The hot sawdust directly absorbs or blots the wax from the surface upon contact with the tubes. It also mechanically 'rubs and scours wax from the surface. Various other mechanical meth ds for removing the surface film of wax are possible provided rubbing, scouring or blotting operations are included. .It is also-true that various other absorbent materials can be employed in place of sawdust in this operation, such as bran, paper scraps and the like The film of wax may also be sufliciently removed'by dissolving thesame in a solvent such as gasoline.

,Such processes are.included in the term mechanically removing.

Treatment of the wax impregnated paper tubes in the wax removing device of Figs. 1, 2 and 3, followed by rumbling in sawdust or the like, constitutes another refinement which may be regardzd as my preferred method of preparing the tubes for the application of the pyroxylin coating composition. As described'in my acknowledged copending application, Serial No. 264,967, removalof the superficial film of unabsorbed wax from the surface of the waxed tubes may be accomplished by heating the tubes to around 250 to 260 F. for a period of about nine minutes and agitating or spinning the shells in a centrifugal or other rotary device. Rinsing the shells with gasoline or the like to remove parafiin from surface fibers is likewise applicable. These mechanical methods of removing the superficial film of unwbsorbed wax give satisfactory results. Y

After the above'described rumbling operation in what I consider the best embodiment of my invention, the paper shot shell tubes are assembled, the caps applied and they are loaded to produce an otherwise finished shell, by operaper cent of the,

tions standard to shot-shell loading. I 'Iheshells are now ready for application of the lacquer composition which is applied by dipping, the operation being conducted by means of the coating machine shown in Figs. 6 and 7. The shells are first mounted in detachable racks which may be similar to the rackshown in Fig. 8. A detail erate with studs, not shown, which are mounted on the edges of the two endless sprocket chains 35-35 of the coating machine.- The racks are thus held in position between the two sprocket chains. A filled rack is shown in position in Figs. 6 and 7 at 52. The motion of the sprocket chain serves to dip the paper tubes of the carcoating machine at 43.

4 I tridges into the wellcontaining coating composition at 39. After'dipping; the cartridges are pulled upward along the drip pan 41 and finally travel horizontally towards the sprocket 46. The

racks of coatedcartridges are removed from the Altogether about'2o minutes is allowed for draining and drying oi the dippedshells before they are removed from the coating machine.

- scribed above are considerably more waterproof than any shellsproduced previous to the introduction of my process; For example, they'are to times as waterproof as shells whose paper tubes have been merely impregnated with paramn alone, While some shells coated with lacquer alone are fairly waterproof they are not I uniformly so. I Any rupture of the coating causes produced by my process are not only consider-' a large decrease in their waterproofness. The

average waterproofness is not high. Such la'cquer coated shells are also commonly too brittle and are inclined to split during'firing. Shells ablymore waterproof but are also not brittle.

The combination of the wax impregnation on the inner layers of the paper shells with the lac.-

quered coating on the outside appears to give the shot-shells certain highly desirable characteristics. The paraffin preserves or increases the natural elasticity of the paper tubes. There appears to be a true combination between the wax inner coating and the lacquer outer coating. The paraflin acts as a plasticizer, impregnating and softening the interior of the paper tube, while the lacquer acts as a strengthening agent on the outside, imparting stillness and rigidity. There is thus a coaction between the two coatings which cooperate to produce the desired result. The combination of the coatings is thus obviously not the mere sum or aggregation of the two coatings. The total weight of the coatings amounts to nearly A the weight of the paper tubes. The coatings thus form an important part of the shell structure itself and are essential for the production of satisfactory shot-shells.

The fact that a pyroxylin lacquer can be made to adhere in cohesive engagement with a paper tube containing wax is indeed surprising. The lack of adherence between a lacquer coating and a greasy or waxy surface 'has been so generally recognized that manufacturers of lacquer commonly place directions on containers to the effect that all traces of wax or grease must be removed prior to application of the lacquer While there has been at least one suggestion in'the literature of coating a wax impregnated shot-shell with celluloid varnish, all attempts to produce satisfactory shells in the manner there described have proved to be futile. These prior coatings were non-adherent. In fact, it is only by the use of my mechanical methods for removing the .continuous superficial film of unabsorbed wax from the surface, combined with the pyroxylin compositions which I employ, that success has fin lly been obtained. I

The majority of lacquer compositions now on the market have at least a small content of hydrocarbon solvents, such as toluol. Such lacquer 7 process unless they are modified by the inclusion of a drying oil, such as'China woodoil- The hydrocarbon content apparently dissolvessome par-- afiin from the paper shot-shells, producing a film" of wax upon the surface of the lacquer. '80 prevents evaporation of the lacquer solyent, the lacquer frequently requiring several days to dry completely. when finally dried the 'surface'is mottled inv appearance and will craze and chip off easily; The inclusion of a drying oil, such as China-wood oil, prevents these difllculties, provided the hydrocarbon content is not too great; 1

It isadvantageous, however, to. employ a lacquer free frbm hydrocarbons'in my process.

In the absence (if-hydrocarbon :solvents in given lacquer composition, theaddition of drying oils such as linseed, hemp 11nd poppy oil will produce satisfactory results in my process, but

coat of lacquer, with or without a drying oil, it is necessary to remove the continuous surfacefllm. of unabsorbed wax from the wax impregnated L paper tubes by the rubbing, wiping, blotting and other mechanical methods outlined previously. 106. As stated in my acknowledged copending, application lacquers in general are satisfactory which are of pyroxylin composition, which are of resinous-pyroxylin composition, which, contain a drying oil, which are free 0! hydrgcarbon solvents, which contain a resin and a drying o'il'such as China-wpod oil, and which contain a;resi n.= and a drying oil and are free from drocarbonsolvents. a

I have found that natural resins, such as ,copal dammar, etc., or ester guns are advantageousingredients of lacquer compositions suitable for my process. 'I also advantageously add a dryingpilto these compositions. Two specific examples; of lacquer compositions suitable for my process are as follows: I

- Per cent- Pyroxylin 1 11.2- 'China-wood 'oil 10.0

Dammar Y -10.0 121') Ethyl alcohol 16. 2 Ethyl acetate 23.4 Butyl acetate 23. 2'. Butyl alcohol 6.0

- Per cent Pyroxylin 11.2 Dibutyl phthalate 3. '7 Blown linseedoil 10. 0 3 Dammar 6.3 Ethyl alcohol 1 15.0 Ethyl acetate i 25. 8 Butyl acetate 22.0 F Butyl alc 6.0

Either of the above compositions applied to a wax impregnated paper tube, suitably treated by a matter of fact, vanish under the extreme con ditions of heat and pressure 0 firing.

aused by rapid While I have specifically described my process as applied to the production of waterproof shotcompositions are not generally satisfactory in my shells, it is obvious that it is applicable to other" technical uses. Paper tubes'of various sorts and sizes can be so treated. The waterproofed tubes. can be employed as containers for chemicals, foodstuffs and the like as well as for other purposes. In all cases it is desirable to cut the tubes to length in order that the wax may be able, to penetrate more rapidly from the ends. It is only necessary to impregnate the tubes with wax at a temperature considerably abovemelting point of the said wax, to remove the surface film of unabsorbed wax by rubbing, dissolving, wiping, blotting and other mechanical operations and to then apply the lacquer coat. It is advantageous to carry out the mechanical removal of the surface film of wax while heating the paper tubes.

It is also desirable to somewhat under-saturate the tubes with wax during the impregnating operation, the wax becoming homogenized throughout the body of the paper tubes during subsequent operations.

This application is in parta continuation of my prior applications, Serial Nos. 92,5 94, filed March 5, 1926 and 264,967, filed March 26, 1928.

What I claim is:

1. A process of treating shot shells which consists in impregnating paper shot shell tubes with paraflin subjecting the impregnated tubes to a temperature of approximately 250 to 260 F. for about nine minutes, and then applying to the tubes a coating of pyroxylin composition.

2. An improved shot gun shell comprising a. tubular, fibrous wax impregnated container, the waxed surface thereof being uniformly and substantially free of a film of unabsorbed wax, and having a dry, hard, cohesive waterproof sheath produced from an applied pyroxylincomposition containing a resin.

3. An improved shot gun shell comprising a tubular, fibrous wax impregnated container, the waxed surface thereof being uniformly and substantially free of a film of unabsorbed wax, and having a dry, hard, cohesive waterproof sheath produced from an applied pyroxylin composition containing a resin and a drying oil such as Chinawood oil.

4. An improved shot gun shell comprising a tubular, fibrous wax impregnated container, the waxed surface thereof being uniformly and substantially free of a film of unabsorbed wax, and having a dry, hard, cohesive waterproof sheath produced from an applied pyroxylin composition containing a resin and being free from hydrocarbon solvents.

5. An improved shot gun shell comprising a. tubular fibrous wax impregnated container, the waxed surface thereof being uniformly and substantially free of a film of unabsorbed wax, and having a dry, hard, cohesive waterproof sheath produced from an applied pyroxylin composition containing a resin and a drying oil and being free from hydrocarbon solvents.

6. In a shot shell, a uniformly wax-impregnated paper container having a fibrous mat surface and an outer sheath of resinous pyroxylin composition in looking engagement with said surface.

7. An improved method of coating shot gun shells which comprises impregnating a paper container with wax, heating such wax impregnated container to a temperature substantially above the melting point of the wax and under agitating conditions to produce a uniform waxed surface free of a film of unabsorbed wax and applying to said film-free surface a pyroxylin lacquer subtubes with wax, heating said tubes to a temperastantially free from hydrocarbon solvents, and allowing said lacquer to dry and harden.

8. An improved method of coating shot gun shells which comprises'impregnating a paper con;/

tainer with wax,- heating such wax impregnated 30 9. An improved method. of coating shotgun shells which comprises impregnating a paper container with wax, heating such wax impregnated container to a temperature substantially above the melting point of the wax and under agitating conditions to produce a uniform waxed surface.v free of a film of unabsorbed wax and applying to said film-free surface a pyroxylin composition containing a resin and a drying oil and allowing the same to dry and harden. I

10. Animproved method of coating shot gun shells which comprises impregnating a paper container with wax, heating such wax impregnated container to a temperature substantially above the melting point of the wax and under agitating conditions to produce a uniform waxed surface free of a film of unabsorbed wax and applying to said film-free surface a pyroxylin composition containing a resin and China-wood oil and allowing the same to dry and harden. V

11. An improved method of coating shot gun shells which comprises impregnating a paper container with over 18 per cent by weightof wax, heating such wax impregnated container at a' temperature substantially above the melting point of such wax to reduce the paraflin content to about 18 per cent and under agitating conditions to produce .a uniform waxed surface free of a film of unabsorbed wax and applying to said film-free surface a coating of pyroxylin lacquer I and allowing the same to dry and harden. V 12. An improved method of coating shot gun shells which comprises making a wax impregnated paper shell, superficially removing the waxby heating to a temperature above its melting point while agitating to produce a fibrous mat surface of uniform wax content and applying a sheath of pyroxylin-resin composition in looking engagement to said mat surface;

13. In the manufacture of shot shells, the steps which comprise impregnating paper shot shell tubes with wax and then mechanically removing any film of unabsorbed wax from the outer surface of the tubes to prepare said surface for the application of a lacquer.

1a. The process of claim 13 wherein the film of unabsorbed wax is mechanically removed by contacting said paper shot shell tubes with a wax-absorbent material.

15. In the manufacture of shot shells the stepswhich comprise impregnating paper shot shell tubes with wax, heating such. wax impregnated tubes to a temperature substantially above the melting point of the wax and under agitating conditions to produce a uniform surface free from a film of unabsorbed wax and capable of firmly retaining an applied lacquer coating.

16. The process of claim 15 wherein the paper shot shell tubes are cut to length prior to impregnation with wax.

1']. In the manufacture of shot shells, the steps which comprise impregnating paper shot shell iao Q hee ' sorbed wax by a'rumbling operation with a wax-'- absorbentniaterial. v 18. The of claim 1'1 whereln'the waxabsorbentmaterial comprises sawdust.

'19-. In the-manufacture of shot shells. the steps which comprise impregnating said tubes with molten wax, rendering uniform the wax content while heating under agitating'conditions and mechanically removing the superficial illm of unab-v sorbed wax, thereafter coating said paper tubes with a pyroxylin lacquer. V

20. In the manufacture. of shot shells, the process which comprises impregnating paper shot\ shell tubeswith wax, mechanically removingany mm of unabsorbed. wax from the outcrjsurfaceof the tubes andapplying to said surface a lacquer of pyroxylin composition.

21'. The process in accordance in which the lacquer containsa drying oil.

' -22. The process in accordancewith claim 20 in which thelacquer islsubgtanti u f Horn solvents for wax.

- 23. In the manufacture of shot shells. the

process which comprises. impregnating paper shot. shell tubes with wax, removing the film of unab sorbed wax from the outer surface of the tubes" and coating said film-free surface with a pyroxyshells which comprises impregnating a paper its claim 20% ing a-fllm of unabsorbed war on the. surface of the tube, treating the waxed, surface 0! the tube with a solvent for the wax to remove from the I 25; .A shot shell comprising a paper tube uniformly imvregnated with waxto the outer sur- 28. A shot shell comprising a paper tube uniformly impregnated with wax to the outer surface, said surface being uniformly and substantially shot shell tube with wax under conditions leav- I face, said surface being mechanically freed-from free from-a film of unabsorbed wax and pro- I.

wax byheating substantially above the conditions prior to applicationof said pyroxylinf composition. A I 27. A, shot shell comprising a paper tube uniformly impregnated to its outer surface with about 18 per cent of wax, said surface being uniformly and substantially free from a film oi unabsorbed wax and provided with a hard dry cohesive sheath produced from an applied py oxylin composition containing a. resin and a drying cil.-

EDWIN J; Johnson;

surfacethe film of unabsorbed wax, and applying to the film-free surfaces pyroxylin'composition. J

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