U.S. patent application number 16/596181 was filed with the patent office on 2020-02-20 for primer diffuser for polymer ammunition cartridges.
This patent application is currently assigned to TRUE VELOCITY IP HOLDINGS, LLC. The applicant listed for this patent is TRUE VELOCITY IP HOLDINGS, LLC. Invention is credited to Lonnie Burrow.
Application Number | 20200056872 16/596181 |
Document ID | / |
Family ID | 57452384 |
Filed Date | 2020-02-20 |
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United States Patent
Application |
20200056872 |
Kind Code |
A1 |
Burrow; Lonnie |
February 20, 2020 |
PRIMER DIFFUSER FOR POLYMER AMMUNITION CARTRIDGES
Abstract
The present invention provides a diffuser cup or ring adapted to
hold a primer used in an ammunition cartridge comprising a bottom
surface sized to fit in a primer recess for an ammunition
cartridge; a diffuser aperture positioned through the bottom
surface and aligned with a flash hole; a cup wall attached to the
bottom surface and extending away from the bottom surface; and an
interior cavity bordered by the cup wall and the bottom surface and
sized to frictionally fit a primer.
Inventors: |
Burrow; Lonnie; (Carrollton,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TRUE VELOCITY IP HOLDINGS, LLC |
Garland |
TX |
US |
|
|
Assignee: |
TRUE VELOCITY IP HOLDINGS,
LLC
Garland
TX
|
Family ID: |
57452384 |
Appl. No.: |
16/596181 |
Filed: |
October 8, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14731731 |
Jun 5, 2015 |
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16596181 |
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14011202 |
Aug 27, 2013 |
9546849 |
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14731731 |
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13292843 |
Nov 9, 2011 |
8561543 |
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14011202 |
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61456664 |
Nov 10, 2010 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F42C 19/0807 20130101;
F42C 19/10 20130101 |
International
Class: |
F42C 19/08 20060101
F42C019/08; F42C 19/10 20060101 F42C019/10 |
Claims
1. A diffuser cup adapted to hold a primer used in an ammunition
cartridge comprising: a bottom surface sized to fit in a primer
recess for an ammunition cartridge; a diffuser aperture positioned
through the bottom surface and aligned with a flash hole; a cup
wall attached to the bottom surface and extending away from the
bottom surface; and an interior cavity bordered by the cup wall and
the bottom surface and sized to frictionally fit the primer.
2. The diffuser cup of claim 1, wherein the diffuser cup comprises
a metal, an alloy, a composite or a polymer.
3. The diffuser cup of claim 1, further comprising an adhesive
applied to the bottom surface to contact a primer.
4. The diffuser cup of claim 1, further comprising an adhesive
applied to the bottom surface to contact the primer recess.
5. The diffuser cup of claim 1, further comprising a primer
positioned in the interior cavity.
6. A diffuser ring adapted to separate a primer and a primer recess
in an ammunition cartridge comprising: a diffuser ring sized to fit
in a primer recess for an ammunition cartridge having a bottom
surface opposite a top surface; and a diffuser aperture positioned
through the bottom surface and the top surface to align with a
flash hole of the ammunition cartridge.
7. The diffuser ring of claim 6, wherein the diffuser ring
comprises a metal, an alloy, a composite or a polymer.
8. The diffuser ring of claim 6, further comprising an adhesive
applied to the bottom surface to contact a primer.
9. The diffuser ring of claim 6, further comprising an adhesive
applied to the bottom surface to contact the primer recess.
10. The diffuser ring of claim 6, further comprising an adhesive
applied to the top surface to contact the primer.
11. The diffuser ring of claim 6, further comprising a primer
positioned in the interior cavity.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Divisional Application of U.S. patent
application Ser. No. 14/731,731 filed on Jun. 5, 2015, which is a
Continuation-in-Part of U.S. patent application Ser. No. 14/011,202
filed on Aug. 27, 2013 now U.S. Pat. No. 9,546,849 issued Jan. 17,
2017, which is a Divisional Application of U.S. patent application
Ser. No. 13/292,843 filed on Nov. 9, 2011 now U.S. Pat. No.
8,561,543 issued Oct. 22, 2013, which claims the benefit of U.S.
Provisional Patent Application Ser. No. 61/456,664, filed Nov. 10,
2010, the contents of each are hereby incorporated by reference in
their entirety.
TECHNICAL FIELD OF THE INVENTION
[0002] The present invention relates in general to the field of
ammunition primers, specifically to compositions of matter and
methods of making and using primers having a diffuser for use with
polymer ammunition cartridges.
STATEMENT OF FEDERALLY FUNDED RESEARCH
[0003] None.
INCORPORATION-BY-REFERENCE OF MATERIALS FILED ON COMPACT DISC
[0004] None.
BACKGROUND OF THE INVENTION
[0005] Without limiting the scope of the invention, its background
is described in connection with primers for polymer cartridge
casing ammunition. Conventional ammunition cartridge casings for
rifles and machine guns, as well as larger caliber weapons, are
made from brass, which is heavy, expensive, and potentially
hazardous. There exists a need for an affordable lighter weight
replacement for brass ammunition cartridge cases that can increase
mission performance and operational capabilities. Lightweight
polymer cartridge casing ammunition must meet the reliability and
performance standards of existing fielded ammunition and be
interchangeable with brass cartridge casing ammunition in existing
weaponry. Reliable cartridge casing manufacturing requires
uniformity (e.g., bullet seating, bullet-to-casing fit, casing
strength, etc.) from one cartridge to the next in order to obtain
consistent pressures within the casing during firing prior to
bullet and casing separation to create uniformed ballistic
performance. Plastic cartridge casings have been known for many
years but have failed to provide satisfactory ammunition that could
be produced in commercial quantities with sufficient safety,
ballistic, handling characteristics, and survive physical and
natural conditions to which it will be exposed during the
ammunition's intended life cycle; however, these characteristics
have not been achieved. Shortcomings of the known plastic or
substantially plastic ammunition include the possibility of the
projectile being pushed into the cartridge casing, the bullet pull
being too light such that the bullet can fall out, the bullet pull
being too insufficient to create sufficient chamber pressure, the
bullet pull not being uniform from round to round, and portions of
the cartridge casing breaking off upon firing or insufficient
sealing about the primer. To overcome the above shortcomings,
improvements in cartridge casing design and performance polymer
materials are needed.
[0006] U.S. Pat. No. 7,610,858 discloses a cylindrical drum design
to eliminate the need for the adhering method in the primer's
design, while providing protection against the effects of
temperature variance, age, and physical movement of the cartridge.
It provides continuous operable positioning of the priming mixture
between the firing pin and the anvil without requiring the addition
of glue to the priming mixture and includes a cylindrical disk with
a shelf for containing an amount of starter priming mixture that
replaces the conical anvil.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention provides a diffuser cup adapted to
hold a primer used in an ammunition cartridge comprising a bottom
surface sized to fit in a primer recess for an ammunition
cartridge; a diffuser aperture positioned through the bottom
surface and aligned with a flash hole; a cup wall attached to the
bottom surface and extending away from the bottom surface; and an
interior cavity bordered by the cup wall and the bottom surface and
sized to frictionally fit a primer. The diffuser cup may be in part
or entirely comprise a metal, an alloy, a composite or a polymer.
The diffuser cup may further include an adhesive applied to the
bottom surface to contact a primer, an adhesive applied to the
bottom surface to contact the primer recess or both. The diffuser
cup may further include a primer positioned in the interior
cavity.
[0008] The present invention provides a diffuser ring adapted to
separate a primer and a primer recess in an ammunition cartridge
comprising a diffuser ring sized to fit in a primer recess for an
ammunition cartridge having a bottom surface opposite a top
surface; and a diffuser aperture positioned through the bottom
surface and the top surface to align with a flash hole of the
ammunition cartridge.
[0009] The diffuser ring may be made in part or entirely from a
metal, an alloy, a composite or a polymer. The diffuser ring may
further include an adhesive applied to the bottom surface to
contact a primer, an adhesive applied to the bottom surface to
contact the primer recess, an adhesive applied to the top surface
to contact the primer or a combination thereof. The diffuser ring
may further include a primer positioned in the interior cavity.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0010] For a more complete understanding of the features and
advantages of the present invention, reference is now made to the
detailed description of the invention along with the accompanying
figures and in which:
[0011] FIG. 1 depicts an exploded view of the polymeric cartridge
casing;
[0012] FIG. 2 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case according to one embodiment of the
present invention;
[0013] FIG. 3 depicts a side, cross-sectional view of a portion of
the polymeric cartridge casing lacking the aperture coating;
[0014] FIG. 4 is a top plan view of a general primer;
[0015] FIG. 5 depicts a cross-sectional elevation view taken along
line 2-2 of the primer in FIG. 4;
[0016] FIGS. 6a and 6b are images of a diffuser adapter;
[0017] FIG. 7 is an exploded image of the diffuser ring that is
placed between the primer and the bottom of the primer recess;
[0018] FIG. 8 is an exploded image of the diffuser cup that at
least partially covers the primer and fits in the primer recess;
and
[0019] FIG. 9 is a cut away image of the diffuser cup that at least
partially covers the primer and fits in the primer recess.
DETAILED DESCRIPTION OF THE INVENTION
[0020] While the making and using of various embodiments of the
present invention are discussed in detail below, it should be
appreciated that the present invention provides many applicable
inventive concepts that can be embodied in a wide variety of
specific contexts. The specific embodiments discussed herein are
merely illustrative of specific ways to make and use the invention
and do not delimit the scope of the invention.
[0021] To facilitate the understanding of this invention, a number
of terms are defined below. Terms defined herein have meanings as
commonly understood by a person of ordinary skill in the areas
relevant to the present invention. Terms such as "a", "an" and
"the" are not intended to refer to only a singular entity, but
include the general class of which a specific example may be used
for illustration. The terminology herein is used to describe
specific embodiments of the invention, but their usage does not
delimit the invention, except as outlined in the claims.
[0022] As used herein, the term "ammunition", "ammunition article",
"munition", and "munition article" as used herein may be used
interchangeably to refer to a complete, assembled round or
cartridge that is ready to be loaded into a firearm and fired,
including cap, casing, propellant, projectile, etc. Ammunition may
be a live round fitted with a projectile, or a blank round with no
projectile and may also be other types such as non-lethal rounds,
rounds containing rubber bullets, rounds containing multiple
projectiles (shot), and rounds containing projectiles other than
bullets such as fluid-filled canisters and capsules. Ammunition may
be any caliber of pistol or rifle ammunition, e.g., non limiting
examples include .22, .22-250, .223, .243, .25-06, .270, .300,
.30-30, .30-40, 30.06, .300, .303, .308, .338, .357, .38, .380,
.40, .44, .45, .45-70, .50 BMG, 5.45 mm, 5.56 mm, 6.5 mm, 6.8 mm, 7
mm, 7.62 mm, 8 mm, 9 mm, 10 mm, 12.7 mm, 14.5 mm, 20 mm, 25 mm, 30
mm, 40 mm and others.
[0023] As used herein, the term "casing" and "case" and "body" are
used interchangeably (e.g., "cartridge casing", "cartridge case"
and "casing body") to refer to the portion of the ammunition that
remains intact after firing and includes the propellant chamber and
may include the primer insert. A cartridge casing may be one-piece,
two-piece, three piece or multi-piece design that includes a mouth
at one end and a primer insert at the other separated by a
propellant chamber.
[0024] The polymeric ammunition cartridges of the present invention
are of a caliber typically carried by soldiers in combat for use in
their combat weapons. The present invention is not limited to the
described caliber and is believed to be applicable to other
calibers as well. This includes various small and medium caliber
munitions, including 5.56 mm, 7.62 mm and .50 caliber ammunition
cartridges, as well as medium/small caliber ammunition such as 380
caliber, 38 caliber, 9 mm, 10 mm, 20 mm, 25 mm, 30 mm, 40 mm, 45
caliber and the like. The cartridges, therefore, are of a caliber
between about 0.05 and about 5 inches. Thus, the present invention
is also applicable to the sporting goods industry for use by
hunters and target shooters.
[0025] A traditional cartridge casing generally has a deep-drawn
elongated body with a primer end and a projectile end. During use,
a weapon's cartridge chamber supports the majority of the cartridge
casing wall in the radial direction, however, in many weapons, a
portion of the cartridge base end is unsupported. During firing,
the greatest stresses are concentrated at the base end of the
cartridge, which must have great mechanical strength. This is true
for both subsonic and supersonic ammunition cartridges.
[0026] Reliable cartridge manufacture requires uniformity from one
cartridge to the next in order to obtain consistent ballistic
performance. Among other considerations, proper bullet seating and
bullet-to-casing fit is required. In this manner, a desired
pressure develops within the casing during firing prior to bullet
and casing separation. Historically, bullets employ a cannelure,
which is a slight annular depression formed in a surface of the
bullet at a location determined to be the optimal seating depth for
the bullet. In this manner, a visual inspection of a cartridge
could determine whether or not the bullet is seated at the proper
depth. Once the bullet is inserted into the casing to the proper
depth, one of two standard procedures is incorporated to lock the
bullet in its proper location. One method is the crimping of the
entire end of the casing into the cannelure. A second method does
not crimp the casing end; rather the bullet is pressure fitted into
the casing.
[0027] Firing pin-initiated primers are employed in ammunition
primarily for initiation of the powder charge. A firing
pin-initiated primer or percussion cap consists of a pressed or
cast impact-sensitive charge of a known type, a so-called anvil
which abuts against the sides of the primer charge which face in
the initiation direction thereof, that is towards the main or
propellant charge which is to be initiated by the primer, and a
protective case or capsule surrounding the other sides of the
primer charge and consisting of at least partly deformable
material. The surface of the primer charge facing the anvil may
also be covered by a readily destructible protective foil which, as
a rule, mainly has a moisture-protective function. On the
initiation of the primer, the casing is, thus, to be deformed by a
firing pin opposite the anvil, so that the primer charge which is
compressed between the anvil and the deformed case, is initiated.
In the primer designs most commonly employed today, the anvil
consists of a bent sheet bridge with gaps on either side thereof in
order that the flame jets from the initiated primer charge will be
able to reach the main or propellant charge. The anvil consists of
a metal body perforated by some means for the passage of the flame
jets. The drawback inherent in both of these basic types of anvil
is that they leave greater or smaller parts of the upper surface of
the primer charge wholly without support, either in the form of
gaps beside the anvil or perforations through the anvil.
[0028] The present invention is a diffuser that adapts a primer to
a polymer cartridge. Generally, the ammunition cartridge includes a
polymer cartridge that has been overmolded over a metal primer
insert that includes a primer recess. The present diffuser is
adapted to fit between the primer recess and abut the interior wall
of the primer recess to separate the primer from the bottom wall of
the primer recess. In another embodiment, the diffuser is adapted
to fit in the primer recess and abut both the side wall and the
bottom wall of the primer recess to separate the primer from the
walls of the primer recess.
[0029] FIG. 1 depicts an exploded view of the polymeric cartridge
casing. A cartridge 10 is shown with a polymer casing 12 showing a
propellant chamber 14 with a forward end opening 16 for insertion
of a projectile (not shown). Polymer casing 12 has a substantially
cylindrical open-ended polymeric bullet-end component 18 extending
from forward end opening 16 rearward to opposite end 20. The
bullet-end component 18 may be formed with coupling end 22 formed
on opposite end 20. Coupling end 22 is shown as a female element,
but may also be configured as a male element in alternate
embodiments of the invention. The forward end of polymeric
bullet-end component 18 has a shoulder 24 forming chamber neck 26.
Polymer casing 12 has a substantially cylindrical opposite end 20.
Coupling end 22 is shown as a female element, but may also be
configured as a male element in alternate embodiments of the
invention. The middle body component (not shown) is connected to a
substantially cylindrical coupling element 30 of the substantially
cylindrical insert 32. Coupling element 30, as shown may be
configured as a male element, however, all combinations of male and
female configurations is acceptable for coupling elements 30 and
coupling end 22 in alternate embodiments of the invention. Coupling
end 22 fits about and engages cylindrical coupling element 30 of a
substantially cylindrical insert 32. The substantially cylindrical
insert 32 includes a substantially cylindrical coupling element 30
extending from a bottom surface 34 that is opposite a top surface
36. When contacted the coupling end 22 interlocks with the
substantially cylindrical coupling element 30, through the coupling
element 30 that extends with a taper to a smaller diameter at the
tip 44 to form a physical interlock between substantially
cylindrical insert 32 and middle body component 28. The
substantially cylindrical insert 32 also has a flange 46 cut
therein and a primer recess 38 and primer flash hole aperture 42
formed therein for ease of insertion of the primer (not shown). A
primer flash hole aperture 42 is located in the primer recess 38
and extends through the bottom surface 34 into the propellant
chamber 14 to combust the propellant in the propellant chamber 14.
When molded the coupling end 22 extends the polymer through the
primer flash hole aperture 42 to form the primer flash hole 40
while retaining a passage from the top surface 36 through the
bottom surface 34 and into the propellant chamber 14 to provide
support and protection about the primer flash hole aperture 42.
[0030] FIG. 2 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case according to one embodiment of the
present invention. A portion of a cartridge suitable for use with
high velocity rifles is shown manufactured with a polymer casing 12
showing a propellant chamber 14. Polymer casing 12 has a
substantially cylindrical opposite end 20. The bullet-end component
18 may be formed with coupling end 22 formed on opposite end 20.
Cylindrical coupling end 22 is shown as a female element, but may
also be configured as a male element in alternate embodiments of
the invention. The middle body component (not shown) is connected
to a substantially cylindrical coupling element 30 of the
substantially cylindrical insert 32. Coupling element 30, as shown
may be configured as a male element, however, all combinations of
male and female configurations is acceptable for coupling elements
30 and coupling end 22 in alternate embodiments of the invention.
Coupling end 22 fits about and engages coupling element 30 of a
substantially cylindrical insert 32. The substantially cylindrical
insert 32 includes a substantially cylindrical coupling element 30
extending from a bottom surface 34 that is opposite a top surface
36. Located in the top surface 36 is a primer recess 38 that
extends toward the bottom surface 34. A primer flash hole 40 is
located in the primer recess 38 and extends through the bottom
surface 34 into the propellant chamber 14. The coupling end 22
extends the polymer through the primer flash hole 40 to form a
flash hole aperture 42 while retaining a passage from the top
surface 36 through the bottom surface 34 and into the propellant
chamber 14 to provide support and protection about the primer flash
hole 40. When contacted the coupling end 22 interlocks with the
substantially cylindrical coupling element 30, through the
cylindrical coupling element 30 that extends with a taper to a
smaller diameter at the tip 44 to form a physical interlock between
substantially cylindrical insert 32 and middle body component 28.
Polymer casing 12 also has a substantially cylindrical open-ended
middle body component 28.
[0031] FIG. 3 depicts a side, cross-sectional view of a portion of
the polymeric cartridge case lacking the aperture coating (not
shown). A portion of a cartridge suitable for use with high
velocity rifles is shown manufactured with a polymer casing 12
showing a propellant chamber 14. Polymer casing 12 has a
substantially cylindrical opposite end 20. The polymer bullet-end
component 18 may be formed with coupling end 22 formed on opposite
end 20. Coupling end 22 is shown as a female element, but may also
be configured as a male element in alternate embodiments of the
invention. The middle body component (not shown) is connected to a
substantially cylindrical coupling element 30 of the substantially
cylindrical insert 32. Coupling element 30, as shown may be
configured as a male element, however, all combinations of male and
female configurations is acceptable for coupling elements 30 and
coupling end 22 in alternate embodiments of the invention. Coupling
end 22 fits about and engages coupling element 30 of a
substantially cylindrical insert 32. The substantially cylindrical
insert 32 includes a substantially cylindrical coupling element 30
extending from a bottom surface 34 that is opposite a top surface
36. Located in the top surface 36 is a primer recess 38 that
extends toward the bottom surface 34. A primer flash hole 40 is
located in the primer recess 38 and extends through the bottom
surface 34 into the propellant chamber 14. The coupling end 22
extends the polymer through the primer flash hole 40 to form a
primer flash hole aperture coating 42 while retaining a passage
from the top surface 36 through the bottom surface 34 and into the
propellant chamber 14 to provide support and protection about the
primer flash hole 40. When contacted the coupling end 22 interlocks
with the substantially cylindrical coupling element 30, through the
coupling element 30 that extends with a taper to a smaller diameter
at the tip 44 to form a physical interlock between substantially
cylindrical insert 32 and middle body component 28. Polymer casing
12 also has a substantially cylindrical open-ended middle body
component 28.
[0032] FIG. 4 depicts a top view of a primer 50. The primer 50
includes the cup 52 having a retaining means 54a, 54b and 54c and
anvil 56.
[0033] FIG. 5 depicts a cross-sectional elevation view taken along
line 2-2 of the primer 50 in FIG. 4. The primer 50 includes the cup
52 having a bottom 58 and side wall 60 that forms an internal
cavity 62 that houses an explosive charge 64. The cup 52 is sized
to frictionally fit a primer aperture (not shown). An insulating
liner 66 is positioned within the cup 50 separating the cup 50 from
the contact 68. A button 70 is positioned in the bottom 58
surrounded by the insulating liner 66 and contacting the contact
68. When a firing pin strikes the primer 50 and crushed the button
70 against the anvil 56, the highly reactive explosive charge is
initiated by the button 70 to produce a high velocity flame that
extends into the flash hole (not shown) and contacts the propellant
(not shown). This is only one embodiment of a primer 50 that may be
used with the present invention and any primer 50 may be used.
[0034] FIGS. 6a and 6b are images of a diffuser adapter. FIG. 6a is
an image of a diffuser ring 72 that is placed between the primer
(not shown) and the bottom of the primer recess (not shown). The
diffuser ring 72 includes a diffuser aperture 74 that aligns with
the flash hole (not shown) and the primer (not shown). FIG. 6b is
an image of a diffuser cup 76 that covers (or at least partially
covers) the primer (not shown) and fits in the primer recess (not
shown). The diffuser cup 76 includes bottom surface 78 that
includes a diffuser aperture 74 that aligns with the flash hole
(not shown) and a cup wall 80 that attaches to the bottom surface
78 to cover the primer (not shown).
[0035] FIG. 7 is an exploded image of the diffuser ring 72 that is
placed between the primer 50 and the bottom of the primer recess
38. The diffuser ring 72 includes a diffuser aperture 74 that
aligns with the flash hole (not shown) and the primer 50.
[0036] FIG. 8 is an exploded image of the diffuser cup 76 that
covers (or at least partially covers) the primer 50 and fits in the
primer recess 38. The diffuser cup 76 includes bottom surface 78
that includes a diffuser aperture 74 that aligns with the flash
hole (not shown) of the primer recess 38. The diffuser cup 76
includes a cup wall 80 that attaches to the bottom surface 78 to
cover the primer 50.
[0037] FIG. 9 is a cut away image of the diffuser cup 76 that
covers (or at least partially covers) the primer 50 and fits in the
primer recess 38. The diffuser cup 76 includes bottom surface 78
that includes a diffuser aperture 74 that aligns with the flash
hole (not shown) of the primer recess 38. The diffuser cup 76
includes a cup wall 80 that attaches to the bottom surface 78 to
cover the primer 50. The diffuser cup 76 and the diffuser ring 72
may be made of a metal or alloy or a polymer composition and may be
combined with some form of suitable sealant. This seal may possibly
be improved by a sealant or by pressing the anvil against the
diffuser cup or the diffuser ring.
[0038] The components may be formed from high-strength polymer,
composite metal, alloys or ceramic. Examples of suitable high
strength polymers include composite polymer materials including a
tungsten metal powder, nylon 6/6, nylon 6, and glass fibers; and a
specific gravity in a range of 3-10. The tungsten metal powder may
be 50%-96% weight. The polymer material also includes about
0.5-15%, preferably about 1-12%, and most preferably about 2-9% by
weight, of nylon 6/6, about 0.5-15%, preferably about 1-12%, and
most preferably about 2-9% by weight, of nylon 6, and about
0.5-15%, preferably about 1-12%, and most preferably about 2-9% by
weight, of glass fibers. It is most suitable that each of these
ingredients be included in amounts less than 10% by weight. The
composition may be made of a modified ZYTEL.RTM. resin, available
from E.I. DuPont De Nemours Co., a modified 612 nylon resin,
modified to increase elastic response. Examples of suitable
polymers include polyurethane prepolymer, cellulose,
fluoro-polymer, ethylene inter-polymer alloy elastomer, ethylene
vinyl acetate, nylon, polyether imide, polyester elastomer,
polyester sulfone, polyphenyl amide, polypropylene, polyvinylidene
fluoride or thermoset polyurea elastomer, acrylics, homopolymers,
acetates, copolymers, acrylonitrile-butadinen-styrene,
thermoplastic fluoro polymers, inomers, polyamides,
polyamide-imides, polyacrylates, polyatherketones,
polyaryl-sulfones, polybenzimidazoles, polycarbonates,
polybutylene, terephthalates, polyether imides, polyether sulfones,
thermoplastic polyimides, thermoplastic polyurethanes,
polyphenylene sulfides, polyethylene, polypropylene, polysulfones,
polyvinylchlorides, styrene acrylonitriles, polystyrenes,
polyphenylene, ether blends, styrene maleic anhydrides,
polycarbonates, allyls, aminos, cyanates, epoxies, phenolics,
unsaturated polyesters, bismaleimides, polyurethanes, silicones,
vinylesters, or urethane hybrids. Examples of suitable polymers
also include aliphatic or aromatic polyamide, polyeitherimide,
polysulfone, polyphenylsulfone, poly-phenylene oxide, liquid
crystalline polymer and polyketone. Examples of suitable composites
include polymers such as polyphenylsulfone reinforced with between
about 30 and about 70 weight percent, and preferably up to about 65
weight percent of one or more reinforcing materials selected from
glass fiber, ceramic fiber, carbon fiber, mineral fillers, organo
nanoclay, or carbon nanotube. Preferred reinforcing materials, such
as chopped surface-treated E-glass fibers provide flow
characteristics at the above-described loadings comparable to
unfilled polymers to provide a desirable combination of strength
and flow characteristics that permit the molding of head-end
components. Composite components can be formed by machining or
injection molding. Finally, the cartridge case must retain
sufficient joint strength at cook-off temperatures. More
specifically, polymers may have one or more of the following
properties: Yield or tensile strength at -65.degree. F.>10,000
psi Elongation-to-break at -65.degree. F.>15% Yield or tensile
strength at 73.degree. F.>8,000 psi Elongation-to-break at
73.degree. F.>50% Yield or tensile strength at 320.degree.
F.>4,000 psi Elongation-to-break at 320.degree. F.>80%.
Commercially available polymers suitable for use in the present
invention thus include polyphenylsulfones; copolymers of
polyphenylsulfones with polyether-sulfones or polysulfones;
copolymers and blends of polyphenylsulfones with polysiloxanes;
poly(etherimide-siloxane); copolymers and blends of polyetherimides
and polysiloxanes, and blends of polyetherimides and
poly(etherimide-siloxane) copolymers; and the like. Particularly
preferred are polyphenylsulfones and their copolymers with
poly-sulfones or polysiloxane that have high tensile strength and
elongation-to-break to sustain the deformation under high interior
ballistic pressure. Such polymers are commercially available, for
example, RADEL.RTM. R5800 polyphenylesulfone from Solvay Advanced
Polymers. The polymer can be formulated with up to about 10 wt % of
one or more additives selected from internal mold release agents,
heat stabilizers, anti-static agents, colorants, impact modifiers
and UV stabilizers.
[0039] One of ordinary skill in the art will know that many
propellant types and weights can be used to prepare workable
ammunition and that such loads may be determined by a careful trial
including initial low quantity loading of a given propellant and
the well known stepwise increasing of a given propellant loading
until a maximum acceptable load is achieved. Extreme care and
caution is advised in evaluating new loads. The propellants
available have various burn rates and must be carefully chosen so
that a safe load is devised.
[0040] The description of the preferred embodiments should be taken
as illustrating, rather than as limiting, the present invention as
defined by the claims. As will be readily appreciated, numerous
combinations of the features set forth above can be utilized
without departing from the present invention as set forth in the
claims. Such variations are not regarded as a departure from the
spirit and scope of the invention, and all such modifications are
intended to be included within the scope of the following
claims.
[0041] It is contemplated that any embodiment discussed in this
specification can be implemented with respect to any method, kit,
reagent, or composition of the invention, and vice versa.
Furthermore, compositions of the invention can be used to achieve
methods of the invention.
[0042] It will be understood that particular embodiments described
herein are shown by way of illustration and not as limitations of
the invention. The principal features of this invention can be
employed in various embodiments without departing from the scope of
the invention. Those skilled in the art will recognize, or be able
to ascertain using no more than routine experimentation, numerous
equivalents to the specific procedures described herein. Such
equivalents are considered to be within the scope of this invention
and are covered by the claims.
[0043] All publications and patent applications mentioned in the
specification are indicative of the level of skill of those skilled
in the art to which this invention pertains. All publications and
patent applications are herein incorporated by reference to the
same extent as if each individual publication or patent application
was specifically and individually indicated to be incorporated by
reference.
[0044] The use of the word "a" or "an" when used in conjunction
with the term "comprising" in the claims and/or the specification
may mean "one," but it is also consistent with the meaning of "one
or more," "at least one," and "one or more than one." The use of
the term "or" in the claims is used to mean "and/or" unless
explicitly indicated to refer to alternatives only or the
alternatives are mutually exclusive, although the disclosure
supports a definition that refers to only alternatives and
"and/or." Throughout this application, the term "about" is used to
indicate that a value includes the inherent variation of error for
the device, the method being employed to determine the value, or
the variation that exists among the study subjects.
[0045] As used in this specification and claim(s), the words
"comprising" (and any form of comprising, such as "comprise" and
"comprises"), "having" (and any form of having, such as "have" and
"has"), "including" (and any form of including, such as "includes"
and "include") or "containing" (and any form of containing, such as
"contains" and "contain") are inclusive or open-ended and do not
exclude additional, unrecited elements or method steps.
[0046] The term "or combinations thereof" as used herein refers to
all permutations and combinations of the listed items preceding the
term. For example, "A, B, C, or combinations thereof" is intended
to include at least one of: A, B, C, AB, AC, BC, or ABC, and if
order is important in a particular context, also BA, CA, CB, CBA,
BCA, ACB, BAC, or CAB. Continuing with this example, expressly
included are combinations that contain repeats of one or more item
or term, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, and so
forth. The skilled artisan will understand that typically there is
no limit on the number of items or terms in any combination, unless
otherwise apparent from the context.
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