U.S. patent number 3,707,915 [Application Number 05/081,690] was granted by the patent office on 1973-01-02 for wad assembly for shotgun shell.
Invention is credited to Jack A. Kerzman.
United States Patent |
3,707,915 |
Kerzman |
January 2, 1973 |
WAD ASSEMBLY FOR SHOTGUN SHELL
Abstract
A wad assembly for a shotgun shell, including two separately
formed parts, one of which has a portion at one end for receiving
the force of a powder charge, and has a split sleeve portion
projecting toward its opposite end for receiving at least some of
the shot. The second part is receivable within the shot sleeve of
the first part, at a location to transmit axial forces to the shot
charge, and includes a transverse wall for acting against the shot,
and one or more posts which are bendable to changed conditions to
allow for reception of different amounts of shot, and to also
cushion the axial forces produced on firing.
Inventors: |
Kerzman; Jack A. (Glendora,
CA) |
Family
ID: |
22165756 |
Appl.
No.: |
05/081,690 |
Filed: |
October 19, 1970 |
Current U.S.
Class: |
102/451 |
Current CPC
Class: |
F42B
7/08 (20130101) |
Current International
Class: |
F42B
7/08 (20060101); F42B 7/00 (20060101); F42b
007/06 (); F42b 007/08 () |
Field of
Search: |
;102/42,42C,95 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Stahl; Robert F.
Claims
I claim:
1. A wad assembly for use in a shotgun shell case, comprising an
outer part to be received in said case and forming at a first end
of said part a piston for receiving the force of a powder charge
and providing a gas seal with said case, said outer part forming
also a tubular sleeve which is integral with said piston and
projects axially therefrom toward the second end of said part and
to an open end of the sleeve for lining said case and receiving at
least a portion of a shot charge, said sleeve having slits
extending along its side wall from said open end of the sleeve
toward said piston to divide at least a portion of the sleeve into
a plurality of fingers adapted to spread outwardly on firing, said
piston forming a wall extending across an inner end of said sleeve,
and an inner part insertible axially into said sleeve through said
open end thereof in a direction toward said piston and operable to
transmit axial forces from said piston to said shot charge, said
piston being constructed to block movement of said inner part into
said sleeve in the opposite direction from said first end of said
outer part, said inner part forming a second wall disposed across
said sleeve at a location spaced from said wall of the piston for
transmitting forces to said shot charge, said inner part forming at
least one post integral with and projecting from said second wall
toward said piston and constructed to bend to a changed condition
upon exertion of said axial forces but to yieldingly resist said
bending in a relation cushioning the transmission of said forces,
said outer part forming a first detent shoulder, and said inner
part forming a coacting second detent shoulder adapted to be forced
past said first shoulder upon said insertion of said inner part
axially through said open end of the sleeve toward said piston and
to then retain said inner part against reverse movement in a
direction away from said piston and out said open end of the
sleeve.
2. A wad assembly as recited in claim 1, in which said slits formed
in said sleeve terminate short of said first detent shoulder, said
sleeve being circularly continuous at the location of said first
shoulder.
3. A wad assembly as recited in claim 1, in which both of said
shoulders are essentially annular.
4. A wad assembly as recited in claim 1, in which said inner part
includes a plurality of said posts projecting generally axially
inwardly from said second wall, and a connecting structure integral
with said posts and connecting together their axially inner ends
and located near said piston, said posts being bendable at
locations axially between said second wall and said connecting
structure.
5. A wad assembly as recited in claim 1, in which there are a
plurality of said posts extending generally axially near said
sleeve and having axially inner end portions connected together and
portions intermediate the opposite ends of said posts which are
bendable radially inwardly away from the sleeve and generally
toward one another by the force of said powder charge.
6. A wad assembly as recited in claim 1, in which said first detent
shoulder is formed in said outer part at a location near said wall
formed by the piston, and said second detent shoulder is formed on
said inner part at essentially the axially inner end of said post
near said wall formed by the piston.
7. A wad assembly as recited in claim 1, in which said inner part
forms a third wall at the axially inner end of said post generally
parallel to said second wall and receivable adjacent said wall
formed by the piston.
8. A wad assembly as recited in claim 1, in which said inner part
forms a third wall at the axially inner end of said post generally
parallel to said second wall and receivable adjacent said wall
formed by the piston, said second detent shoulder being formed on
said inner part at the periphery of said third wall.
9. A wad assembly as recited in claim 1, in which said inner part
forms a plurality of said posts projecting generally axially
inwardly from said second wall, and carrying at axially inner ends
of said posts a third wall extending generally parallel to said
second wall and receivable adjacent said wall formed by the piston,
said posts being connected at opposite ends to said second and
third walls near their peripheries and having portions
longitudinally intermediate said ends which are deformable radially
inwardly and generally toward one another by said force of the
powder charge, said first detent shoulder being formed within a
circularly continuous portion of said sleeve axially beyond the
inner extremities of said slits in the sleeve, said second detent
shoulder being formed on the periphery of said third wall.
10. A wad assembly as recited in claim 9, in which said
longitudinally intermediate portions of said posts are deflectible
generally toward one another to positions overlapping one another
but offset laterally to avoid interferring contact with one
another.
11. A wad assembly for use in a shotgun shell case, comprising an
outer part to be received in said case and forming at a first end
of said part a piston for receiving the force of a powder charge
and providing a gas seal with said case, said outer part forming
also a tubular sleeve which is integral with said piston and
projects axially therefrom toward the second end of said part and
to an open end of the sleeve for lining said case and receiving at
least a portion of a shot charge, said sleeve having slits
extending along its side wall from said open end of the sleeve
toward said piston to divide at least a portion of the sleeve into
a plurality of fingers adapted to spread outwardly on firing, said
piston forming a wall extending across an inner end of said sleeve,
and an inner part insertible axially into said sleeve through said
open end thereof in a direction toward said piston and operable to
transmit axial forces from said piston to said shot charge, said
wall of the piston being constructed and positioned to block
movement of said inner part into said sleeve in the opposite
direction from said first end of said outer part, said inner part
forming a second wall disposed across said sleeve at a location
spaced from said wall of the piston, a plurality of posts formed
integrally with said second wall and projecting therefrom in a
generally axially inward direction toward said piston, and a
connecting structure formed integrally with said posts at the
axially inner ends thereof and connecting said inner ends of the
posts together at a location adjacent said wall formed by the
piston, said posts having portions axially intermediate said second
wall and said connecting structure and axially intermediate the
opposite ends of said posts and which are constructed to bend to a
changed condition upon exertion of said axial forces but to
yieldingly resist said bending in a relation cushioning the
transmission of said forces.
12. A wad assembly as recited in claim 9, in which said connecting
structure is a third wall spaced from and generally parallel to
said second wall and positioned adjacent said piston, said second
and third walls being circular and of a diameter corresponding
approximately to the internal diameter of said sleeve.
13. A wad assembly as recited in claim 11, in which said posts have
their ends connected to said second wall and said structure at
locations near said sleeve, said intermediate portions of the posts
being bendable generally radially inwardly away from the sleeve by
the force of said powder charge.
14. A wad assembly for use in a shotgun shell case, comprising an
outer part to be received in said case and forming at a first end
of said part a piston for receiving the force of a powder charge
and providing a gas seal with said case, said outer part forming
also a tubular sleeve which is integral with said piston and
projects axially therefrom toward the second end of said part and
to an open end of the sleeve for lining said case and receiving at
least a portion of a shot charge, said sleeve having slits
extending along its side wall from said open end of the sleeve
toward said piston to divide at least a portion of the sleeve into
a plurality of fingers adapted to spread outwardly on firing, said
piston forming a wall extending across an inner end of said sleeve,
and an inner part insertible axially into said sleeve through said
open end thereof in a direction toward said piston and operable to
transmit axial forces from said piston to said shot charge, said
inner part forming a second wall disposed across said sleeve at a
location spaced from said wall of the piston for transmitting
forces to said shot charge, said inner part forming a plurality of
posts integral with and projecting from said second wall toward
said piston and constructed to bend to changed conditions upon
exertion of said axial forces but to yieldingly resist said bending
in a relation cushioning the transmission of said forces, said
posts including two posts which are located at opposite sides of an
axially extending plane located therebetween and which have
portions intermediate the ends of the two posts which are bendable
generally toward one another and toward said plane to positions at
which they both intersect said plane and overlap one another in the
direction of their flexure but are offset laterally within said
plane with respect to one another in a relation avoiding
substantial interference with one another.
15. A wad assembly as recited in claim 14, in which there are two
pairs of said posts at opposite sides respectively of said plane
and bendable toward the plane to positions at which both pairs
intersect the plane and overlap one another but are offset
laterally to avoid interference with one another.
16. A wad assembly as recited in claim 15, in which the posts of
one of said pairs intersect said plane laterally between the posts
of the other pair.
17. A wad assembly as recited in claim 15, in which the posts of
one of said pairs intersect said plane laterally between the posts
of the other pair, said posts of said other pair being constructed
to flare relatively apart as they bend, in a relation to receive
the posts of said one pair therebetween.
18. A wad assembly as recited in claim 15, in which the posts of
one of said pairs intersect said plane laterally between the posts
of the other pair, there being a strap extending laterally between
and interconnecting said posts of said one pair.
Description
BACKGROUND OF THE INVENTION
This invention relates to an improved wad assembly to be positioned
between the powder and shot charge in a shotgun shell.
Though in recent years a number of different types of specially
shaped wad structures have been placed on the market for use in
shotgun shells, each of these prior arrangements with which I am
familiar has had one or more distinct disadvantages in actual use.
As an example, one of the currently available wads is a one piece
unit having a powder contacting portion at one end, a shot
receiving cup at its opposite end, and a deformable portion between
the two first mentioned portions for cushioning the forces exerted
by the powder upon firing. One difficulty which has been
encountered with this type of one piece structure has been the
tendency for the powder contacting portion of the device to cock
relative to the shot receiving cup upon firing, as a result of the
inability of the resiliently deformable intermediate portion to
maintain the two ends of the device in properly fixed relative
orientation. If the powder contacting portion does cock on firing,
some of the force of the gases of combustion may leak past that
portion, or may exert their forces unevenly in a manner adversely
affecting the shot pattern, accuracy, firing range, or other firing
characteristics of the gun or shell.
Another disadvantage of most prior wad structures has resided in
their lack of versatility for use with different sizes of shot
charge, different types of shell case, etc. This limitation has
been especially bothersome to persons who like, when possible, to
reload used shells in order to reduce the cost of shooting. Since
most of the types of wads heretofore on the market have been
adapted for use with only one size shot charge, and in only one
type of shell case, a person who reloads shells has in the past
found it necessary to keep on hand a number of different types of
wads, in order to be in a position to reload different types of
shells.
SUMMARY OF THE INVENTION
The present invention provides a unique wad assembly which very
effectively overcomes the above and other disadvantages of the
various prior wad structures of which I am aware. For one thing, a
wad assembly embodying the invention is designed to positively
preclude any possibility of cocking of the portion of the wad which
receives the gas force, relative to the portion of the wad which
contains the shot charge, to thereby avoid the above discussed
possibility of gas leakage, pattern distortion, etc. Additionally,
the wad assembly is constructed to enable its use in different
types of shells, and especially with different sizes of shot load,
so that a person who reloads shells can employ the single type of
wad assembly in a number of different types of casing and different
load size situations. At the same time, the wad is very simple in
structure and therefore inexpensive to manufacture and use.
Structurally, a wad assembly embodying the invention includes two
separately formed parts, which are secured together for handling as
a single unit during the loading procedure. A first of these parts
of the assembly has a portion at one of its ends which functions
essentially as a piston against which the force of the gases of
combustion produced by the propellant powder are exerted upon
firing. The opposite end of the same part forms a longitudinally
slit sleeve or cup within which a portion or all of the shot charge
is received, and which functions to protect the shot against
contact with the barrel of the gun on firing.
The second part of the assembly is contained within the shot
protecting sleeve of the first part, and is axially compressible to
cushion the gas force as applied to the shot charge. This second
part also is compressible axially to a variable extent during
loading, in a manner enabling automatic accommodation to and
reception of different sizes of shot load, to thus permit the above
discussed use of the single wad assembly with varying loads within
a relatively wide size range.
To achieve these results, the second or internal part of the
assembly is molded to a unique shape in which it forms a generally
transverse wall adapted to engage and exert force against the shot
charge on firing, and one or more posts or columns which project
from that wall and are bendable to changed conditions in response
to the exertion of axial forces thereon, in a manner yieldingly
resisting axial compression of that second part. Preferably, the
posts are connected at their second ends to a second generally
transverse wall, which bears against a transverse surface on the
first or outer part of the assembly. Also, it is desirable that the
second or inner part be yieldingly retained within the first part
in an appropriate manner by suitable detenting means, to hold the
two parts together while handling them during a loading
operation.
BRIEF DESCRIPTION OF THE DRAWING
The above and other features and objects of the invention will be
better understood from the following detailed description of the
typical embodiments illustrated in the accompanying drawing in
which:
FIG. 1 is an axial sectional view through a shot gun shell having a
first form of wad assembly constructed in accordance with the
invention;
FIG. 2 is a view similar to FIG. 1, but showing the shell as it
appears when provided with a heavier shot charge than that employed
in FIG. 1;
FIG. 3 is an enlarged fragmentary representation of a portion of
the device of FIG. 1 or FIG. 2 after firing and during movement
through the gun barrel;
FIG. 4 is an enlarged side view of the inner part of the wad
assembly, taken on line 4--4 of FIG. 1;
FIGS. 5 and 6 are transverse sections taken on lines 5--5 and 6--6
respectively of FIGS. 1 and 2;
FIG. 7 is a section taken on line 7--7 of FIG. 4;
FIG. 8 is a side view, partially broken away, of the outer part of
the wad assembly shown separately;
FIG. 9 is a perspective view of the inner element of a variational
form of wad assembly embodying the invention;
FIG. 10 is a view similar to FIG. 3 but showing the changed
structure of FIG. 9; and,
FIG. 11 is a horizontal section taken on line 11--11 of FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMeNT
Referring to the first form of the invention shown in FIGS. 1 to 8,
I have illustrated at 10 a shot gun shell having a conventional
case 11 which includes the usual tubular side wall or body element
12 and a metal cup or base element 13 extending across one end of
the case. Within cup 13, there may be provided an annular filler
element 14 containing a primer 15 adapted to ignite the propellant
powder 16 when unit 15 is struck by the firing pin of a gun. As
will be apparent, the main body or side wall element 12 of the
shell case is both internally and externally cylindrical, and it
has its upper end crimped inwardly at 17 to close the upper end of
the shell.
The present invention is particularly concerned with the
construction of a wad assembly 18 which is provided within the shot
case, and which is interposed between the powder charge 16 and the
shot charge 19. Assembly 18 consists of two separately formed
elements, including a first outer part 20, and an axially
compressible second part 21 located within the interior of part 20.
Both of these parts 20 and 21 may be molded from a suitable
resinous plastic material which is so compounded or selected as to
be essentially stiff or rigid in the thicker regions of the two
parts, but to be resiliently deformable at the thinner regions. A
presently preferred plastic material for this purpose is
polyethylene.
The outer part 20 of the wad assembly has a lower portion 22
forming a wall disposed transversely across the interior of tubular
side wall element 12 of the shell case, and shaped to form
essentially a piston which is forced axially from the shell case by
the pressure of the gases of combustion from propellant charge 16
upon firing. This piston portion 22 of part 20 may have an upper
essentially planar surface 23 disposed perpendicular to axis 24 of
the shell, and may have a concave undersurface 25 which is centered
about and symmetrical with respect to axis 24 and defines a piston
cup having an annular peripheral downwardly projecting reduced
thickness edge 26 forming a sealing lip of the cup. At its
underside, portion 22 of the outer part 20 of the wad assembly fits
directly over and contacts the upper surface of the mass of
propellant powder 16. Externally, portion 22 has an outer straight
cylindrical surface 27 of a diameter corresponding to the internal
diameter of side wall or body element 12 of the case, and fitting
closely within that side wall element in annularly sealed
relation.
Projecting upwardly from the periphery of lower piston portion 22
of the outer part 20 of the wad assembly, the material of part 20
forms a tubular shot protector sleeve 28. The outer surface 29 of
the sleeve is of straight cylindrical configuration, centered about
axis 24, and forms an upward continuation of cylindrical outer
surface 27 of the lower portion 22 of part 20. Thus, the outer
surface of sleeve 28 is a close fit within, and lines, the inner
surface of side wall element 12 of the case. The inner surface 30
of sleeve 28 is also of straight cylindrical shape, and centered
about axis 24, and disposed parallel to and concentric with outer
surface 29. The side wall of sleeve 28 is very thin radially, and
therefore is relatively freely flexible. This side wall is also
split longitudinally by a series of circularly spaced axial slits
31 into a series of arcuate segments or fingers 32, which are
adapted to be flexed outwardly to a flaring condition by the
resistance of the air as soon as they leave the gun barrel after
firing.
At a location spaced upwardly just slightly above the plane of
upper transverse surface 23 of the lower portion 22 of part 20, the
tubular sleeve 28 may contain an annular inwardly projecting detent
shoulder or bead 33, centered about axis 24 of the shell. As will
appear, this detent shoulder is utilized to retain the second part
21 of the wad assembly within the interior of part 20. Preferably,
shoulder 33 is rounded or of gradually curving configuration at
both its upper and lower sides, as seen best in FIG. 3. Also, it is
desirable that the lower ends 34 of the longitudinal slits 31 in
sleeve 28 terminate at a level just above the location of shoulder
or bead 33, in order that the side wall of the lower portion of the
sleeve may be circularly continuous at the location of the bead,
and therefore may serve its detenting function effectively. The
upper end of sleeve 28 may be cut off transversely, to form an
upper edge 35 of the sleeve lying in a plane disposed perpendicular
to axis 24 of the shell, and which edge may extend upwardly to
substantially the location of the inturned crimped top portion 17
of the shell case.
The inner part 21 of the wad assembly 18 of the first form of the
invention is molded to the configuration illustrated in FIG. 1, in
which it occupies a very substantial portion of the axial extent of
sleeve 28, but not the entire length of the sleeve, to leave room
at the upper end of the sleeve for reception of a relatively small
load of shot 19. Part 21 includes two essentially rigid upper and
lower transverse discs 36 and 37, interconnected by a first pair of
deformable resilient posts 38 and 39 at a first side of the shell,
and a second pair of similar posts 40 and 41 at the opposite side
of the shell. These posts are molded integrally with the two
transverse end walls or discs 36 and 37, and are thinner than those
discs, and in particular thin enough to deform in the manner
illustrated in FIGS. 2 and 3. The discs themselves are
substantially rigid or stiff, to avoid substantial deformation
prior to or during firing. Each of the discs may have an outer
cylindrical peripheral surface 42 or 43 which is a close fit within
the interior of sleeve 28. This surface 43 of the lower disc 37 has
a diameter slightly greater than the minimum diameter of the detent
rib 33, so that it must be forced axially past that rib upon
insertion of part 21 into part 20, with slight radial expansion of
the rib during movement of disc 37 therepast, to thereby
resiliently retain the lower disc 37 and the rest of part 21 in the
FIG. 1 assembled position of reception within part 20. As seen best
in FIG. 3, the periphery of disc 37 may be cut away annularly at 44
to a slightly reduced diameter to receive and coact with detent rib
or projection 33 in a most effective holding relation, and in a
manner enabling positioning of the rib 33 very close to the plane
of transverse surface 23 of part 20. When part 21 is in its fully
inserted position of FIG. 1 within part 20, the undersurface 45 of
bottom wall or disc 37 is received and held in engagement with
surface 23 of part 20, while at the same time rib or detent
projection 33 is in engagement downwardly against the periphery of
disc 37, as shown.
Each of the bendable connector posts 38, 39, 40 and 41 is elongated
vertically between the two discs 36 and 37, and is preshaped to
bend in a predetermined direction and manner upon imposition of
axial compressive forces against part 21. For example, to describe
specifically the configuration of the right hand post 39 of FIG. 1,
as that post advances downwardly from top disc 36 it forms first an
inwardly inclined straight portion 46, which at approximately the
vertically midway point merges with an oppositely and outwardly
inclined straight portion 47 connected at its lower end to bottom
disc 37. As will be apparent, the opposite inclinations of the two
upper and lower portions 46 and 47 of post 39, and the resulting
essentially V-shaped configuration of the post as a whole,
preconditions the post for bending in a predetermined lateral
direction upon exertion of compressive force against part 21. That
is, upon such compression, post 39 tends to bend in the manner
illustrated in FIGS. 2 and 3 at the vertically intermediate
location 48, which constitutes the juncture of upper and lower
portions 46 and 47 and the apex of the V formed by these portions.
To further assure bending of the post in only the desired
predetermined direction, the post is given a cross-section such as
that illustrated in FIG. 5, 6 and 7, which cross-section is uniform
along the entire vertical extent of the post, and which
cross-section is characterized by a reduced thickness dimension t
in the desired direction of bend, and a somewhat greater width
dimension w in a direction perpendicular to the direction of bend.
In FIG. 5, the plane within which post 39 is initially bent, and
within which it continues to bend upon exertion of axial
compressive force against part 21, is defined by the broken line 50
of that figure. To discuss the cross-section of post 39 more
specifically, this cross-section may be defined by a straight line
51 which is perpendicular to the bend plane 50 and faces in the
direction in which the post bends, and at the opposite side two
angular lines 52 and 53 meeting at the plane 50 of the bend.
All of the four posts 38 through 40 have approximately the same
configuration as that discussed above in connection with post 39,
except that the posts are oriented differently to bend in
predetermined different relative directions upon compression of
part 21. This difference in orientation of the various posts is
perhaps described best by reference to two perpendicular
diametrical planes designated 54 and 55 in FIG. 5. The two posts 38
and 39 are connected to discs 36 and 37 to the right of plane 55,
and are constructed to bend leftwardly toward that plane, while the
other two posts are connected to the discs at the left side of
plane 55, and bend rightwardly toward that plane. Posts 38 and 39
are located at opposite sides of and are symmetrical with respect
to the second plane 54 of FIG. 5, and similarly the two posts 40
and 41 form a pair of such posts, and are located at opposite sides
of and symmetrical with respect to plane 54. The previously
mentioned plane of bend 50 of post 39, and the corresponding plane
of bend 50a of post 38, are generally parallel to one another so
that the two posts bend leftwardly in generally parallel relation
and at opposite sides of plane 54. To retain posts 38 and 39
against separation during such bending these posts may be
interconnected at a location near their centers by a thin integral
connecting strap 56 which moves leftwardly in FIGS. 1 and 5 as the
posts bend.
The two posts 40 and 41 are so oriented that their planes of bend
50b and 50c (corresponding to plane 50 of post 39) diverge away
from one another and away from plane 54 as they advance rightwardly
in FIG. 5. This divergence is sufficiently great to cause the
central bend regions of posts 40 and 41 to be offset laterally
outwardly with respect to the bends of the two posts 38 and 39 when
the part 21 is fully compressed to FIG. 3 condition. That is, the
bends of the two posts 38 and 39 are received between and overlap
the bends of the two widely flaring posts 40 and 41 in the fully
compressed condition of FIG. 3 (broken line condition of FIG. 6).
In order to allow this flaring action, there is of course no strap
interconnecting posts 40 and 41 and corresponding to the strap 56
which connects posts 38 and 39. All of the posts are thin enough in
the direction t to enable the desired bending movement through the
FIG. 2 condition and to the FIG. 3 condition, but at the same time
are thick enough in that direction to offer very substantial
resistance to such bending of the posts, and thereby yieldingly and
resiliently resist compression of part 21. Upon release of axial
forces exerted against part 21, this part tends to return to its
initial axially extended condition of FIG. 1, by virtue of the
resilience of the polyethylene or other material of which the part
is formed.
To now describe the manner of use of the discussed wad assembly of
FIGS. 1 to 8, assume first of all that the shell case 11 is empty,
and that it is desired to load the shell with a relatively small
amount of shot. With the upper end of the shot case open, a
predetermined measured quantity of the propellant powder 16 is
first filled into the shell case, following which the wad assembly,
including both of the parts 20 and 21 held together by detent ring
33, is inserted into the case as a unit above the powder. Next, the
measured amount of shot 19 is inserted into the upper end of sleeve
28, and the upper end of the case is crimped over at 17 to close
the shell. Upon firing of the shell, within a gun barrel, the force
exerted by the gases of combustion produced by propellant powder 16
act against the piston portion 22 of part 20 to force the entire
wad and the following shot charge 19 axially out of the forward end
of the shot case, and through the barrel for ultimate exit from the
barrel. The annular sealing lip 26 of part 20 is by virtue of its
reduced thickness sufficiently deformable to be forced radially
outwardly in annular fluid type sealing engagement with the inner
surface of the shot case, and with the gun barrel itself, to
thereby positively prevent the escape of any of the gases of
combustion axially past the wad structure. The axial forces are
transmitted to inner wad part 21 by engagement of surface 23 with
bottom disc 37 of part 21, and are transmitted through posts 39
through 41 of part 21 to the upper disc 36, and then to shot charge
19. These forces are great enough to cause rapid axial compression
of part 21 to the reduced dimension condition illustrated in FIG.
3, in which the posts 38 through 41 are bent to their fully
deformed condition, and discs 36 and 37 are in very closely spaced
relation. The resistance to such bending which is offered by the
posts effectively cushions the transmissions of axial forces from
the wad assembly to the shot charge, in a manner minimizing recoil
of the gun, preventing damage to the shot charge, and assuring most
effective transmission of all of the power of the gases of
combustion thereto. As the wad and shot move axially through the
barrel, all of the shot is further protected by confinement within
the interior of sleeve 28, which thereby protects the shot against
contact with the gun barrel itself. As soon as the shot and wad
leave the forward end of the gun barrel, the resistance to wad
movement offered by the contacted air causes the segments or
fingers 32 of the forward sleeve portion 28 of the wad assembly to
flare outwardly away from one another to an expanded condition out
of contact with the shot charge, with the air resistance then
immediately slowing the wad assembly to avoid any further contact
of the wad with the shot charge.
If it is desired to utilize a heavier shot load in the shell, this
may be done by merely measuring the desired increased amount of
shot and inserting it to the condition illustrated in FIG. 2, with
the inner part 20 of the wad being forcibly compressed by forces
exerted against it through the shot during loading, and until the
part 21 has reached a suitable partially compressed condition in
which the upper end of the shot case can be crimped closed with the
proper load in the case. Thus, any desired load from a very light
load such as that shown in FIG. 1 to a relatively heavy load can be
provided as desired by the shooter. When the shell of FIG. 2 is
fired, the part 21 completes its compression to the FIG. 3
condition, to again cushion the transmission of forces to the shot
charge and thereby attain the advantages previously discussed.
FIGS. 9 to 11 show fragmentarily a variational form of the
invention which may be considered as identical with the form of
FIGS. 1 to 8 except with regard to the construction of the inner
axially compressible part 21' of the wad assembly, corresponding to
part 21 of FIGS. 1 to 8. The outer element 20' of the FIGS. 9 to 11
wad assembly may be the same as part 20 of FIGS. 1 to 8.
Inner wad element 21' includes two typically identical circular
parallel discs 36' and 37', whose upper and lower parallel surfaces
are disposed transversely of axis 24' of the shell and wad
assembly, and whose outer cylindrical surfaces 42' and 43' are
dimensioned to be close fits within the inner cylindrical surface
30' of part 20'. The lower disc 37' may be of a thickness to fit
axially between detenting rib 33' of part 20' and transverse
surface 23' of that part, to snap past rib 33' and thereby detent
part 21' within part 20' in the same manner discussed in connection
with the first form of wad assembly.
Instead of the four connecting posts 38, 39, 40 and 41 of FIGS. 1
to 8, the arrangement of FIGS. 9 to 11 utilizes only two generally
axial posts 38' and 39', molded integrally with and interconnecting
the two spaced transverse discs 36' and 37' at diametrically
opposite locations with respect to axis 24'. These posts 38' and
39' are initially molded to the configuration illustrated in broken
lines in FIG. 10, and are axially compressible to the full line
condition of that figure, but have resilience tending to normally
return the posts toward their initial broken line condition. To
describe that initial shape more specifically, post 38' has two
parallel radially inner and outer surfaces 57 and 58 which in
advancing downwardly from upper disc 36' first advance gradually
radially inwardly toward axis 24' to a vertically central location
59, and then advance progressively radially outwardly at an
opposite angularity as they approach bottom disc 37'. The second
post 39' is of the same generally V-shaped configuration, but is
reversed so that the vertically central portions 59 and 59' of the
two posts project toward one another. As seen in FIG. 11, the
horizontal cross sectional configuration of each of the posts 38'
and 39' is elongated, to have a width dimension w' in a direction
perpendicular to a predetermined axial plane 54' which is
considerably greater than the thickness dimension t' parallel to
that plane, to thus facilitate bending of the posts toward one
another. The plane 54' may be considered as the plane in which the
broken line axially extended representation of inner wad element
21' in FIG. 10 is taken. Thus, the relatively thin V-shaped posts
have an initial deflection toward one another, and upon axial
compression of element 21' increase that bent condition toward the
full line condition of FIG. 10. It is noted that, in
contradistinction to the posts of the first form of the invention,
the posts 38' and 39' of FIGS. 9 to 11 are never deflected far
enough to reach or pass one another, but rather even in the fully
compressed condition shown in full lines in FIG. 10 have their
vertically intermediate portions 59 and 59' either spaced slightly
from one another or barely touching, to avoid interference with one
another. At the locations at which the posts are connected to end
discs 36' and 37', the ends of the posts are spaced slightly
inwardly from the periphery of the discs, as illustrated for
example at 60 in FIG. 9, to avoid interference by the posts with
annular detenting engagement of the upper surface of lower disc 37'
with detenting rib 33' of the outer element 20'.
The arrangement of FIGS. 9 to 11 is utilized in the same manner
discussed in connection with FIG. 8. That is, powder is first
filled into the lower portion of the outer shell case, following
which the wad assembly 20'-21' is placed in the case, with a
desired load of shot being applied above the wad assembly, and with
inner wad element 21' being compressed against its resilience to an
intermediate condition such as that shown in FIG. 2 if a heavy load
of shot is to be employed. The shot and wad are retained in this
condition by crimping of the upper end of the case. Upon firing,
the resilient inner element 21' is further compressed to the full
line condition of FIG. 10, to take up a portion of the shock of the
propellant charge, and the wad assembly and shot then move axially
through the barrel for discharge therefrom, and for ultimate
separation of the parts of the wad assembly from the shot by virtue
of the resistance offered to the wad assembly by the air, as
discussed previously.
While certain specific embodiments of the present invention have
been disclosed as typical, the invention is of course not limited
to these particular forms, but rather is applicable broadly to all
such variations as fall within the scope of the appended
claims.
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