U.S. patent application number 12/775021 was filed with the patent office on 2012-07-12 for modular case ammunition and methods of assembly.
Invention is credited to Vin Battaglia.
Application Number | 20120174813 12/775021 |
Document ID | / |
Family ID | 43050466 |
Filed Date | 2012-07-12 |
United States Patent
Application |
20120174813 |
Kind Code |
A1 |
Battaglia; Vin |
July 12, 2012 |
MODULAR CASE AMMUNITION AND METHODS OF ASSEMBLY
Abstract
A hybrid ammunition cartridge for a firearm is includes a
substantially cylindrical casing defining a body portion having a
neck at a forward end and a base at a rearward end, the base
including a rim. A projectile is mounted in the neck. Brass is used
in the casing at the neck to hold the projectile at the proper
crimp. Brass is also used in the rim to house the primer and to
provide a surface at which a hook or any suitable mechanism can be
used to extract the cartridge from the firearm. The remaining body
portion is then manufactured from a composite material having
suitable mechanical properties.
Inventors: |
Battaglia; Vin; (Easton,
CT) |
Family ID: |
43050466 |
Appl. No.: |
12/775021 |
Filed: |
May 6, 2010 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61175906 |
May 6, 2009 |
|
|
|
Current U.S.
Class: |
102/464 ;
102/430; 86/23 |
Current CPC
Class: |
F42B 33/001 20130101;
F42B 5/26 20130101 |
Class at
Publication: |
102/464 ; 86/23;
102/430 |
International
Class: |
F42B 5/02 20060101
F42B005/02; F42B 33/02 20060101 F42B033/02; F42B 5/285 20060101
F42B005/285 |
Claims
1. A method of manufacturing a hybrid ammunition body, said method
comprising: providing a casing formed from a first material, said
casing defining an interior area; providing a charge vessel formed
from a second material; providing a propellant in an interior area
defined by said charge vessel; and inserting said charge vessel
into said casing; wherein said casing defines a first distal end
portion adapted to receive a projectile; and wherein said charge
vessel is removably retained in said casing.
2. The method of claim 1, wherein said first material is metal and
said step of providing said casing includes forming said casing, at
least in part, by drawing and extruding said metal.
3. The method of claim 1, wherein said casing defines a second
distal end portion opposite said first distal end portion, said
second distal end portion defining a pocket adapted to receive a
primer, said casing further defining a channel extending into said
interior area.
4. The method of claim 3, further comprising hermetically sealing
said channel.
5. The method of claim 3, further comprising inserting a primer in
said pocket.
6. The method of claim 3, wherein said first material is metal,
wherein said step of providing said casing further includes forming
said casing, at least in part, by drawing and extruding said metal,
and wherein said pocket is formed by folding a portion of said
second distal end into said interior area.
7. The method of claim 1, wherein said first material is brass and
said second material is a polymer.
8. The method of claim 3, wherein said first distal end portion and
said second distal end portion are joined by at least two strips
extending therebetween.
9. The method of claim 8, wherein said at least two strips define
at least two openings therebetween.
10. The method of claim 1, wherein said step of inserting said
charge vessel into said casing includes: holding said casing using
a fixture, presenting said charge vessel to an opening defined by
said casing, urging said charge vessel into said opening, and
compressing said charge vessel into said casing to seat said charge
vessel in said casing.
11. The method of claim 10, further comprising inserting a
projectile into said casing.
12. A method of assembling live ammunition, said method comprising
the steps of: retrieving a casing from a casing inventory;
retrieving a charge vessel from a charge vessel inventory;
inserting said charge vessel directly into said casing to provide
an assembled casing and charge vessel; inserting a primer into said
assembled casing and charge vessel; and applying at least one of a
thermal barrier and a waterproof coating to said assembled casing
and charge vessel.
13. The method of claim 12, further comprising puncturing said
charge vessel to cause said primer to be in communication with a
propellant in said charge vessel.
14. The method of claim 13, wherein said step of puncturing said
charge vessel comprises puncturing a blister gate.
15. The method of claim 12, further comprising inserting a
projectile into said assembled casing and charge vessel.
16. The method of claim 12, further comprising sizing said
assembled casing and charge vessel to cause an outer surface of
said charge vessel to be flush with an outer surface of said
casing.
17. A hybrid ammunition cartridge, comprising: a casing formed from
a first material and having a base portion defining a pocket
therein; a charge vessel formed from a second material inserted
directly into said casing, a propellant located in said charge
vessel; and a projectile mounted in said casing; wherein said
hybrid ammunition cartridge can be rendered live upon an insertion
of a primer in communication with said propellant.
18. The hybrid ammunition cartridge of claim 17, wherein at least a
portion of said charge vessel is exposed through at least a portion
of said casing.
19. The hybrid ammunition cartridge of claim 18, wherein said
casing comprises said base portion, at least two strips extending
from said base portion, and a neck attached to said at least two
strips.
20. The hybrid ammunition cartridge of claim 19, wherein said
casing includes a hardness gradient along a length thereof.
21. The hybrid ammunition cartridge of claim 20, wherein a material
of said base portion of said casing is defined in part by a
particular hardness value.
22. The hybrid ammunition cartridge of claim 20, wherein a material
of said casing intermediate said base portion and said neck is
defined in part by a particular hardness value.
23. The hybrid ammunition cartridge of claim 20, wherein a material
of said neck is defined in part by a particular hardness value.
24. The hybrid ammunition cartridge of claim 17, wherein said base
portion includes a rim extending peripherally around said base
portion.
25. The hybrid ammunition cartridge of claim 17, wherein said first
material of said casing is a metal.
26. The hybrid ammunition cartridge of claim 17, wherein said
second material of said charge vessel comprises a polymer
material.
27. The hybrid ammunition cartridge of claim 26, wherein said
polymer material is selected from the group consisting of
polyphenylsulfone, polystyrene, polypropylene, acrylonitrile
butadiene styrene, polyvinyl chloride, polyethylene, polyester
terephthalate, polymethylmethacrylate, polyamide,
styrene-acrylonitrile, and combinations of the foregoing
materials.
28. A method of manufacturing a hybrid ammunition body, said method
comprising: providing a casing formed from a first material, said
casing defining an interior area; molding a charge vessel into said
interior area defined by said casing, said charge vessel being
formed from a second material; and providing a propellant in an
interior area defined by said charge vessel; wherein said casing
defines a first distal end portion adapted to receive a
projectile.
29. The method of claim 28, wherein said first material is metal
and said step of providing said casing includes forming said
casing, at least in part, by drawing and extruding said metal.
30. The method of claim 28, wherein said casing defines a second
distal end portion opposite said first distal end portion, said
second distal end portion defining a pocket adapted to receive a
primer, said casing further defining a channel extending from said
pocket into said interior area.
31. The method of claim 30, further comprising hermetically sealing
said channel.
32. The method of claim 30, further comprising inserting a primer
in said pocket.
33. The method of claim 30, wherein said first material is metal,
wherein said step of providing said casing further includes forming
said casing, at least in part, by drawing and extruding said metal,
and wherein said pocket is formed by folding a portion of said
second distal end into said interior area.
34. The method of claim 28, wherein said first material is brass
and said second material is a polymer.
35. The method of claim 30, wherein said first distal end portion
and said second distal end portion are joined by at least two
strips extending therebetween.
36. The method of claim 35, wherein said at least two strips define
at least two openings therebetween.
37. The method of claim 28, wherein said step of molding said
charge vessel includes: providing a mold defining a mold cavity
therein, positioning said casing in said mold cavity, said casing
defining an open neck portion, said core being inserted through
said open neck portion, said core and an inner surface of said mold
cavity cooperating to define a void therebetween, disposing a
polymer in said void, upon said polymer being cured, removing said
core, and removing said ammunition body from said mold.
38. The method of claim 37, wherein said step of disposing said
polymer in said void comprises vacuum forming softened polymer
around said core.
39. The method of claim 37, wherein said step of disposing said
polymer in said void comprises injection molding said polymer
around said core.
40. The method of claim 28, wherein said step of molding said
charge vessel comprises blow molding said charge vessel.
41. The method of claim 28, wherein said step of molding said
charge vessel comprises compression molding said charge vessel.
42. The method of claim 28, wherein said step of molding said
charge vessel comprises vacuum forming said charge vessel.
43. An ammunition body, comprising: a casing formed from a first
material, said casing defining an interior area; a charge vessel
formed from a second material, said charge vessel being positioned
in said interior area defined by said casing; a propellant located
in an interior area defined by said charge vessel; and wherein said
casing includes a first distal end portion defining a pocket
therein adapted to receive a primer.
44. The ammunition body of claim 43, wherein said casing defines a
channel extending from said pocket into said interior area.
45. The ammunition body of claim 43, wherein said charge vessel
includes a blister gate in communication with said channel.
46. The ammunition body of claim 43, further comprising a primer
located in said pocket.
47. The ammunition body of claim 46, further comprising a hermetic
seal on said primer.
48. The ammunition body of claim 43, wherein said casing includes a
second distal end portion generally opposite said first distal end
portion, and wherein said casing includes at least two strips
extending between said first and second distal ends, at least two
openings in said casing being located between said first and second
strips.
49. The ammunition body of claim 43, further comprising a rim
machined into said base portion of said casing.
50. The ammunition body of claim 43, wherein outer surfaces of said
casing and said charge vessel are flush with each other.
51. The ammunition body of claim 43, wherein said first material is
metal and said second material is polymeric.
52. A hybrid ammunition cartridge, comprising: a casing formed from
a first material and having a base portion defining a pocket
therein; a charge vessel formed from a second material molded
directly into said casing, a propellant located in said charge
vessel; and a projectile mounted in said casing; wherein said
hybrid ammunition cartridge can be rendered live upon an insertion
of a primer in communication with said propellant.
53. The hybrid ammunition cartridge of claim 52, wherein at least a
portion of said charge vessel is exposed through at least a portion
of said casing.
54. The hybrid ammunition cartridge of claim 53, wherein said
casing comprises said base portion, at least two strips extending
from said base portion, and a neck attached to said at least two
strips.
55. The hybrid ammunition cartridge of claim 54, wherein said
casing includes a hardness gradient along a length thereof.
56. The hybrid ammunition cartridge of claim 55, wherein a material
of said base portion of said casing is defined in part by a
particular hardness value.
57. The hybrid ammunition cartridge of claim 55, wherein a material
of said casing intermediate said base portion and said neck is
defined in part by a particular hardness value.
58. The hybrid ammunition cartridge of claim 55, wherein a material
of said neck is defined in part by a particular hardness value.
59. The hybrid ammunition cartridge of claim 52, wherein said base
portion includes a rim extending peripherally around said base
portion.
60. The hybrid ammunition cartridge of claim 52, wherein said first
material of said casing is metal.
61. The hybrid ammunition cartridge of claim 52, wherein said
second material of said charge vessel comprises polymer.
62. The hybrid ammunition cartridge of claim 61, wherein said
polymer material is selected from the group consisting of
polyphenylsulfone, polystyrene, polypropylene, acrylonitrile
butadiene styrene, polyvinyl chloride, polyethylene, polyester
terephthalate, polymethylmethacrylate, polyamide,
styrene-acrylonitrile, and combinations of the foregoing materials.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Patent Application No. 61/175,906, filed on May 6, 2009, the
content of which is incorporated herein by reference in its
entirety.
TECHNICAL FIELD
[0002] The present invention relates to ammunition and, more
particularly, to ammunition that can be assembled in a modular
fashion from separate components and methods for assembling such
ammunition.
BACKGROUND OF THE INVENTION
[0003] Standard ammunition cartridges for firearms are typically
unitary in construction with the structural components of the
cartridge being made from metal. In general, the cartridge includes
four sections, namely, a casing of a generally cylindrical shape
and terminated at a rearward end by a rim, a propellant contained
in the casing, a primer located at the rearward end, and a bullet
or projectile frictionally held in a forward end of the casing. The
casing is sized to a particular caliber, which closely approximates
the diameter of the projectile and is less than the diameter of the
bore defined by the barrel of the firearm through which the
projectile moves. When the cartridge is in a firing chamber located
at a rearward end of the bore, operating the firearm causes the
primer to be ignited (e.g., via impact from a firing pin), which in
turn ignites the propellant (usually gunpowder). Gases from the
ignition of the gunpowder, when contained, increase the pressure
within the casing and cause it to expand. As the casing expands, it
seals against the wall resulting in a buildup of pressure in the
casing. The built-up pressure causes the projectile to separate
from the casing and travel through and out of the bore. The empty
casing can then be removed from the chamber.
[0004] At present most small arms ammunition is manufactured with
drawn brass casings. Brass generally allows for proper neck
retention of the projectile, provides suitable elastic qualities,
and has acceptable abrasion characteristics, thereby minimizing
damage to the internal surfaces of the firearm.
[0005] One of the material properties of brass that makes it
suitable for use in casings is its elasticity. During firing of the
cartridge, large loads are imparted to the casing. The elasticity
of the material of the casing allows the casing to quickly deform
under pressure to provide a suitable seal in the firing chamber and
then to quickly return to its original (or near original)
condition. This quality, which is known as the "springback" of the
casing, facilitates the extraction of the casing from the firing
chamber. Without sufficient springback, the casing would
plastically deform, thereby hindering or preventing extraction of
empty casings.
[0006] Another desirable material property of brass is that it
limits the cook off of cartridges. Cook off, also known as
thermally-induced firing, occurs when the propellant is ignited due
to heat in the surrounding environment. Cook off is especially
limiting in automatic weapons, although semi-automatic weapons can
also be affected. This is due at least in part to a final round
being fed to the firing chamber after the trigger is released. The
round will be "cooked off" if the temperature in the firing
chamber, due to the firing cycle, is sufficiently high to cause the
propellant to ignite. The use of brass as the casing material
inhibits the amount of heat transferred from the firing chamber
through the wall of the casing to the propellant, thus minimizing
the opportunity for cook off to occur.
[0007] The brass casing in a standard cartridge typically comprises
a substantial portion of the total weight of the cartridge. For
example, in a standard 5.56 mm (NATO) cartridge, the brass accounts
for about half of the total weight of the cartridge. Any reduction
in the weight of the cartridge beyond the nominal weight would
enable a person carrying large quantities of rounds to either be
laden with less weight or to carry additional cartridges.
SUMMARY OF THE INVENTION
[0008] In one aspect, a hybrid ammunition cartridge for use in a
firearm is disclosed herein. This hybrid ammunition cartridge
includes a substantially cylindrical skeleton casing defining a
body portion having a neck at a forward end and a base at a
rearward end, the base including a rim. A projectile is mounted in
the neck of the skeleton casing. A suitable material such as (but
not limited to) brass is used in the skeleton casing at the neck to
frictionally retain the projectile at the proper crimp. This
suitable material can also be used in the rim to house the primer
and to provide a surface at which a suitable mechanism can be used
to extract the cartridge from the firearm. As will be explained in
greater detail below, a charge vessel, manufactured from a polymer
having suitable mechanical properties, is located in the skeleton
casing. The polymer weighs less than traditional cartridge
materials such as brass, thereby resulting in a reduction in
cartridge weight.
[0009] In another aspect, the present invention resides in a method
for manufacturing a hybrid ammunition body. This method includes
providing a skeleton casing formed from a first material, the
skeleton casing defining an interior area and a first distal end
portion adapted to frictionally receive a projectile. A charge
vessel is also provided and is molded from a second material. The
charge vessel is removably positioned in, and retained by the
skeleton casing. A propellant is located in an interior area
defined by the charge vessel.
[0010] In still another aspect, the present invention resides in a
method of assembling live ammunition. The method includes the steps
of retrieving a skeleton casing from a casing inventory; retrieving
a charge vessel from a charge vessel inventory; inserting the
charge vessel into the skeleton casing so that the charge vessel is
retained therein, thereby providing an assembled skeleton casing
and charge vessel. A primer is inserted into the assembled skeleton
casing and charge vessel, and a thermal barrier and/or a waterproof
coating is applied thereto.
[0011] In another aspect, the present invention resides in a hybrid
ammunition cartridge. Such a cartridge includes a skeleton casing
formed from a first material. The skeleton casing includes a base
portion defining a pocket therein. A charge vessel formed from a
second material is inserted into the skeleton casing. A propellant
is located in the charge vessel, and a projectile is frictionally
mounted in an end of the skeleton casing. The hybrid ammunition
cartridge can be rendered live upon insertion of a primer, at least
a portion of which is in communication with the propellant.
[0012] In another aspect, a method of manufacturing a hybrid
ammunition body includes providing a skeleton casing formed from a
first material, the skeleton casing defining an interior area. A
charge vessel is molded into the interior area defined by the
skeleton casing. The charge vessel is formed from a second
material. A propellant is located in an interior area defined by
the charge vessel, and a projectile is positioned in and
frictionally retained by a first distal end portion of the skeleton
casing.
[0013] In yet another aspect, the present invention resides in an
ammunition body including a skeleton casing formed from a first
material, the skeleton casing defining an interior area. A charge
vessel is formed from a second material, the charge vessel being
positioned in the interior area defined by the skeleton casing. A
propellant is located in the charge vessel. The skeleton casing
also includes a first distal end portion defining a pocket therein
adapted to receive a primer.
[0014] In another aspect, the present invention resides in a hybrid
ammunition cartridge including a skeleton casing formed from a
first material and having a base portion defining a pocket therein.
A charge vessel is formed from a second material molded directly
into the skeleton casing. A propellant is located in the charge
vessel, and a projectile is frictionally mounted in the skeleton
casing. The hybrid ammunition cartridge can be rendered live upon
insertion of a primer, at least a portion of which is in
communication with the propellant.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is perspective view of a modular cartridge of the
present invention.
[0016] FIG. 2 is sectional view of the modular cartridge of FIG.
1.
[0017] FIG. 3 is a flow chart illustrating a first method of
forming a skeleton casing of a modular cartridge of the present
invention.
[0018] FIG. 4 is a flow chart illustrating a second method of
forming a skeleton casing of a modular cartridge of the present
invention.
[0019] FIG. 5 is a side sectional view of a skeleton casing of a
modular cartridge made by the method of FIG. 3.
[0020] FIG. 6 is a top sectional view of the skeleton casing of the
modular cartridge made by the method of FIG. 3.
[0021] FIG. 7 is a side sectional view of a skeleton casing of a
modular cartridge made by the method of FIG. 4.
[0022] FIG. 8 is a top sectional view of the skeleton casing of the
modular cartridge made by the method of FIG. 4.
[0023] FIG. 9 is a perspective view of a charge vessel.
[0024] FIG. 10 is a schematic representation of a dynamic insertion
process of the present invention.
[0025] FIG. 11 is a flow chart illustrating a process of
dynamically inserting a charge vessel into a skeleton casing.
[0026] FIG. 12 is a flow chart illustrating a first method of
assembling live ammunition.
[0027] FIG. 13 is a schematic representation of a press used in a
direct molding process of assembling a modular cartridge of the
present invention.
[0028] FIG. 14 is a flow chart illustrating a second method of
assembling live ammunition.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] Referring to FIGS. 1 and 2, a modular cartridge for use in a
firearm is shown generally at 10 and comprises a skeleton casing 12
and a charge vessel 14 located in an interior area defined by the
skeleton casing. A projectile 16 is mounted (e.g., frictionally) in
a neck 18 at a forward end of the skeleton casing. The skeleton
casing 12 includes a base 20 having a rim 22 that defines a primer
pocket 26. A primer is positioned in the primer pocket 26 for
igniting a propellant carried in the charge vessel 14.
[0030] As shown in FIG. 2, the skeleton casing 12 defines a channel
27 via which the primer positioned in the primer pocket 26 is in
communication with the charge vessel 14.
[0031] As illustrated in FIG. 3, the skeleton casing 12 may be
formed from a suitable material such as, but not limited to, brass
via a metal stamping operation 30 in which a flat blank is taken
from a continuous coil and separated into two target portions for
the neck and rim, each portion being separately drawn and extruded
into the form of the skeleton casing. In this operation 30, raw
material is obtained in an acquisition step 32. If not already done
so, the raw material is cut or otherwise formed into strips and
manipulated in a formation step (if necessary) to have a uniform
thickness or elevation. The skeleton casing 12 is then formed in a
manufacturing step 36 in which the strips are folded to define the
primer pocket 26. A secondary step 38 is then performed in which
the rim 22 is machined, any desired cutting is performed, and the
channel 27 extending from the primer pocket 26 to the interior of
the skeleton casing 12 is formed. Degreasing operations may also be
performed.
[0032] In another embodiment as is shown in FIG. 4, the skeleton
casing 12 may be formed via a multi-elevation stamping operation 40
from a multi-elevation strip in which the material at one end of
the strip is thicker than the material at the other end and in
which the difference in elevation is either a constant taper or a
flat-taper-flat configuration. In this operation 40, raw material
is obtained in an acquisition step 32. If not already done so, the
raw material is then cut or otherwise formed into strips that are
thicker (more elevation) at one end than the other in an
engineering step 42. One manner of engineering the raw material is
via the use of a planish mill. Subsequent to the engineering step
42, a manufacturing step 44 is carried out in which a skeleton
casing 12 having a solid primer pocket 26 is formed. After the
manufacturing step 44, a secondary step 46 is then performed in
which the rim 22 is machined, any desired cutting is performed, and
a channel extending from the primer pocket 26 to the interior of
the skeleton casing 12 is formed. Degreasing operations may also be
performed.
[0033] Referring now to FIGS. 5 and 6, the skeleton casing 12
manufactured using the metal stamping operation 30 is a
substantially cylindrical member defined by a wall 48 and has two
elongated openings 50 extending lengthwise along generally opposing
sides of the cylindrical member and in the wall intermediate the
neck 18 and the base 20. The peripheral edge of the rearward
surface of the base 20 forms the rim 22. As can be seen in FIG. 6,
an interior surface of the wall 48 is tapered such that the wall is
thicker at the rearward end and thinner at the forward end. The
degree of taper is determined by the particular manufacturing
process. In this embodiment, the material used to fabricate the
skeleton casing 12 is folded via the manufacturing step 36 to
define the primer pocket 26.
[0034] As can be best seen in FIG. 5, the edges 52 of each opening
intermediate the forward and rearward ends of the skeleton casing
12 define strap arm portions 56 that connect the neck 18 and the
base 20. Each strap arm portion 56 defines a slight "S" bend that
improves flexing of the skeleton casing 12 and facilitates the
insertion of the charge vessel 14. Also, the "S" bends of the strap
arm portions 56 allow for the provision of additional length or
stretch, which increases the amount of allowable interference
between the skeleton casing 12 and the charge vessel 14. In any
embodiment, the openings 50 allow a substantial amount of material
to be removed from the casing, thereby reducing the weight of the
casing.
[0035] Referring now to FIGS. 7 and 8, the skeleton casing 12
manufactured from the multi-elevation strip of the multi-elevation
stamping operation 40 comprises a substantially cylindrical member
also having two elongated openings 50. In this embodiment, however,
the material used to fabricate the skeleton casing 12 is tooled
accordingly to provide a solid primer pocket 26 (no folded
material). The skeleton casing 12 of this second embodiment
provides a hardness gradient having a value that is greater than
the skeleton casing of the folded embodiment. Furthermore, material
used to manufacture this skeleton casing 12 has a split elevation,
is taper planed, rolled, or otherwise manipulated to provide for
the multiple thicknesses or elevations in the material.
[0036] As can be seen in FIG. 7, the edges 52 of each opening 50
again define strap arm portions 56 that connect a neck 18 and a
base 20, as with the embodiment of FIGS. 5 and 6. Again, the strap
arm portions 56 are configured to define slight "S" bends to
facilitate several factors in the manufacturing process.
[0037] In either of the above-described methods of forming the
skeleton casing 12, the primer pocket 26 in the base 20 of the
skeleton casing allows the primer to be press fit into the primer
pocket. The present invention is not limited in this regard,
however, as other configurations are within the scope of the
present invention. The specific types of the other configurations
depend upon the actual hardness of the material in the area of the
primer pocket 26 and whether an extrusion process can reliably
retain a standard press fit type of primer. If such a primer cannot
be reliably retained, an alternate construction may be used (for
example, the primer may be mechanically fastened or the press fit
type of primer may be augmented using mechanical fasteners).
Furthermore, in order to afford a margin of safety and to
accommodate the logistics of handling and transportation of the
materials used in construction, the primer configuration may be
otherwise changed in consideration of the manufacturing process
such that the cartridge 10 is not "live" until the primer is
inserted.
[0038] The projectile 16 can be of any suitable configuration (for
example, hollow point, armor piercing, tracer, and the like). The
neck 18 in which the projectile 16 is mounted is appropriately
sized. One advantage of providing the neck 18 of the cartridge 10
as described herein is that projectile retention values
commensurate with current practice can be achieved to yield
ballistics data that is equivalent or superior to ballistics data
of non-modular cartridges.
[0039] The areas proximate the neck 18 and the base 20 are
connected via strap arm portions 56. The areas at which the strap
arm portions 56 connect to the neck area and base area define
points of articulation for the rotation of the neck 18 and base 20
about the common centerline C. The present invention is not limited
to the specific configuration as shown, as the strap arm portions
56 are modifiable to facilitate any articulable rotation of the
neck 18 and base 20 that is desired for a specific design of the
cartridge 10.
[0040] Referring now to FIG. 9, the charge vessel 14, which is
located in the skeleton casing 12, can be manufactured via a stand
alone molding process. After being molded, the charge vessel 14 is
charged with the propellant, purged of any air, sealed with foil,
and stored as a component for incorporation into the skeleton
casing 12. In the alternative, the charge vessel 14 can be
insert-molded directly into the skeleton casing 12. In this
embodiment, any flashing is removed from the charge vessel 14, a
thermal waterproof coating can be applied, and the assembled charge
vessel and skeleton casing 12 are stored as a component. The stand
alone molding process of molding the charge vessel 14 is preferable
for a method of assembling the modular cartridge 10 of the present
invention using dynamic insertion techniques (in which the charge
vessel is dynamically inserted into the skeleton casing 12 after
being molded). For at least the dynamic insertion method, the
charge vessel 14 can be molded using the stand alone molding
process in a basic single cavity mold, and the inside shape of the
charge vessel can be designed to increase the velocity of the
projectile 16 upon firing.
[0041] At least in the dynamic insertion methods of the present
invention, the charge vessel 14 is molded from a polymer and holds
a desired mass of propellant depending on the type and size of the
finished cartridge 10. The weight savings of the modular ammunition
of the present invention is attributed at least in part to the
density of the polymer used. The polymer selected is considered in
view of the characteristics of the final product, such
characteristics including mold shrinkage factors and the like. One
polymer found to be suitable is a polyphenylsulfone sold as RADEL
R-5000, which is available from Solvay Advanced Polymers, L.L.C.,
of Alpharetta, Ga.
[0042] Referring now to FIG. 10, the charge vessel 14 can be
dynamically inserted into the skeleton casing 12. The charge vessel
14 may include a molded blister gate 62 on the rearward end thereof
to receive the primer. The outer surfaces of the charge vessel 14
may be relatively smooth, or they may include contours and reliefs
or the like to comport with the inner surfaces of the skeleton
casing 12 such that after insertion of the charge vessel into the
skeleton casing, the contours and reliefs provide a substantially
flush outer diameter to the cartridge. The flush outer diameter of
the cartridge 10 may facilitate belt feeding of the cartridges and
may also ensure efficient extraction of the cartridge during a
firing cycle.
[0043] Referring now to FIGS. 10 and 11, a process outlining the
dynamic method of inserting the charge vessel 14 into the skeleton
casing 12 is shown generally at 70 in FIG. 11 and is hereinafter
referred to as "process 70." In general, the skeleton casing 12 is
securely retained, and the charge vessel 14 is presented to the
skeleton casing through one of the openings between the strap arm
portions 56 in the direction of an arrow 64 (FIG. 10). The charge
vessel is compressed, and the skeleton casing 12 is moved to allow
the charge vessel to "slide into" the skeleton casing. An
interference fit is thereby created to capture the charge vessel 14
in the skeleton casing 12. This differs from conventional
ammunition manufacturing practice in that with the above-described
components, components of an individual cartridge can be
manufactured at different times and/or in different locations,
stored (if desired), and assembled as desired (for example, in a
just-in-time scenario).
[0044] In process 70, the charge vessel 14 is presented to the
skeleton casing 12 in a suitable orientation via tooling and
various fixtures. The rim 22 of the base 20 is held fast using a
collet. The start point of insertion occurs when the charge vessel
14 makes contact with the skeleton casing 12, which is likely to be
proximate the area where the strap arm portions 56 meet the neck
18. The charge vessel 14 is urged into the skeleton casing 12 and
downward at an angle until the charge vessel is seated in the
skeleton casing.
[0045] The seated charge vessel 14 is sized with a die in a sizing
step. In this sizing step, the edges of the strap arm portions 56
are radiused, which thereby traps the charge vessel 14 within the
skeleton casing 12. At this time, the charge vessel 14 carries the
propellant, with the propellant being dispensed to the charge
vessel prior to its insertion into the skeleton casing 12 and being
retained therein via the blister gate in the primer pocket region.
After being purged of air and the blister gate being put into
place, a foil member is ultrasonically welded over the primer
pocket. By doing so, the charge vessel 14 is effectively sealed,
thereby allowing for an extended shelf life.
[0046] After being sized, the assembled casing 12 and charge vessel
14 could remain as a subcomponent without a projectile and/or
without a primer. By allowing the cartridge 10 to remain in this
semi-completed state, beneficial features in integration and
logistics can be realized. In particular, the type of projectile
can be changed to accommodate last-minute changes in the desired
use. Also, semi-completed cartridges can be more easily shipped and
stored due to their lighter weight and reduced volume. The final
assembly can occur when the projectile and/or the primer are fitted
to the charge vessel/skeleton casing subassembly. Additionally, the
just-in-time aspect of subcomponent assembly has distinct
advantages, particularly with regard to the life of ammunition and
the costs of demilling live ammunition that does not pass proof
testing (the deliberate over-pressuring of ammunition to verify
that the ammunition will not explode in an unexpected manner upon
firing). With JIT manufacturing, as much as about 80% of the costs
associated with demilling live ammunition can be eliminated.
[0047] Referring now to FIG. 12, a system for the assembly of live
ammunition is shown generally at 80 and is hereinafter referred to
as "system 80." System 80 uses JIT principles and fragments the
manufacturing process and distributes portions to various parties,
thereby allowing for simultaneous subcomponent building.
[0048] In the system 80, inventory is pulled in a pulling step 82.
In the pulling step 82, the skeleton casings 12 and the loaded
charge vessels 14 are retrieved from storage or otherwise obtained.
Three additional steps can then be undertaken, either
simultaneously or sequentially. These three steps include a step of
puncturing the blister gate 84, the process 70 of inserting the
charge vessel 14 into the skeleton casing 12, and the step of
inserting the projectile and final sizing 86.
[0049] After the process 70 of inserting the charge vessel 14 into
the skeleton casing 12, a primer installation step 88 is
undertaken. Subsequent to the primer installation, a coating step
90 is carried out in which a thermal barrier and/or waterproof
coating is applied to the primer pocket. This coating step 90 may
include or may be ancillary to the placing of the foil member over
the primer pocket. Once completed, the ammunition is live.
[0050] The system 80 depicted is a process that is truncated and/or
which includes separate independent processes. As such, the need
for a large, unitary manufacturing facility is avoided in favor of
smaller, separate operations, many of which may be carried out by
diverse private entities. Also, production can be streamlined and a
minimum of 50% of demill operations for destroying ammunition that
fails proof testing can be avoided.
[0051] The present invention is not limited to the use of a dynamic
insertion method of inserting a charge vessel 14 into a skeleton
casing 12 (as is shown in process 70 of FIG. 11), as the cartridge
10 can be manufactured by molding the charge vessel into the
skeleton casing. More specifically, the charge vessel 14 may be
insert molded directly into the skeleton casing 12, thereby
circumventing the dynamic insertion method as described above. One
advantage of an insert molding process is that an existing
ammunition production line could be used. Any insert molding
process generally involves providing a suitable polymer and using a
process of extrusion, blow molding, vacuum forming, compression
molding, and/or injection molding to dispose the charge vessel into
the skeleton casing. The present invention is not limited to any of
the foregoing techniques, as other methods, combinations, and
variations thereof are within the scope of the present
disclosure.
[0052] One embodiment of an insert molding process utilizes a press
90 as is shown in FIG. 13. The press 90 employs a machine cycle to
produce the cartridges 10.
[0053] The machine cycle utilizing this press 90 would allow the
skeleton casing to be placed in the mold and the charge vessel to
be molded into the skeleton casing. The charge vessel would then be
filled with the suitable propellant.
[0054] Referring now to FIG. 14, a system for the assembly of live
ammunition is shown generally at 100 and is hereinafter referred to
as "system 100." System 100 is a system of enhancing traditional
ammunition with weight savings and potential cost savings. It
integrates easily into existing SCAMP or other processes and may
also solve problems indicative of other systems in a more efficient
fashion.
[0055] In the system 100, inventory is pulled in a pulling step
102. In the pulling step 82, the skeleton casings 12 and the loaded
charge vessels 14 are retrieved from storage or otherwise obtained.
The skeleton casings 12 and the loaded charge vessels 14 are then
used in a step 104 in which they are substituted for brass casings
in a SCAMP line or other process. A coating step 106 is carried out
in which a thermal barrier and/or waterproof coating is applied to
the primer pocket. Once completed, the ammunition is live.
[0056] Although this invention has been shown and described with
respect to the detailed embodiments thereof, it will be understood
by those of skill in the art that various changes may be made and
equivalents may be substituted for elements thereof without
departing from the scope of the invention. In addition,
modifications may be made to adapt a particular situation or
material to the teachings of the invention without departing from
the essential scope thereof. Therefore, it is intended that the
invention not be limited to the particular embodiments disclosed in
the above detailed description, but that the invention will include
all embodiments falling within the scope of the appended
claims.
* * * * *