[0001] This invention relates to a wad for hunting or competition cartridges.
[0002] As is known, a shotgun cartridge comprises a case inside of which are housed the
projectile, the propellant powder and the wadding.
[0003] The conventional shotgun cartridges on the market use lead or lead alloy, shot since
this material has the ideal characteristics of hardness, weight and workability required
for obtaining good performance when firing. However, these cartridges have considerable
drawbacks from the environmental point of view, since lead is considered very polluting
and harmful to the health of wildlife and responsible for poisoning problems.
[0004] At present, there is therefore a trend to reduce or even ban the use of lead in various
hunting and sporting situations, and to seek alternative materials, such as iron,
glass or wood, in order to produce the most environmentally-friendly cartridges possible.
[0005] As is known, one of the essential elements of the cartridge, in particular if of
the shot projectile type, is the wadding. This has the purpose of transferring the
thrust provided by the pressure of the gas, generated by the combustion of gunpowder,
to the mass of the shot.
[0006] Cartridges with plastic wads are known on the market, which provide good performance
in both shooting and hunting situations. However, even these cartridges have problems
from the environmental point of view, since the plastic wad is fired together with
the projectiles and remains in the environment.
[0007] There are also cartridges with felt wads known on the market that, if on the one
hand solve the problem of environmental pollution, they perform poorly because they
do not contain the gases that are released with the explosion well.
[0008] In the cartridge industry, in particular for target shooting guns or for hunting
use, there is thus a need to produce cartridges that are both environmentally friendly
and that provide good shooting performance.
[0009] The purpose of this invention is to resolve the problems of the known art, taking
into account the needs of the industry.
[0010] This purpose is achieved by a wad according to claim 1 and by a cartridge according
to claim 10.
[0011] The characteristics and advantages of the wad and cartridge according to this invention
will be apparent from the following description, given by way of nonlimiting example,
in accordance with the accompanying figures, in which:
- Figures 1 and 2 show examples of a cartridge according to this invention and, in particular,
a cartridge equipped with the wad of Figure 3 and a cartridge equipped with the wad
of Figure 5;
- Figures 3 and 4 respectively show a side view and a rear axonometric view of a wad
according to this invention, in an embodiment variant;
- Figures 5 and 6 respectively show a side view and a rear axonometric view of a wad
according to this invention, in a further embodiment variant;
- Figures 7, 8 and 9 show respectively a side view, an axonometric rear view, an axonometric
front view of a wad according to this invention, in a still further embodiment variant;
- Figures 10, 11 and 12 show respectively a side view, an axonometric rear view, an
axonometric front view of a wad according to this invention, in a still further embodiment
variant.
[0012] With reference to the accompanying figures, and in particular to Figures 1 and 2,
there is shown a cartridge 100 for shotgun. The cartridge 100 comprises a casing 101,
for example substantially cylindrical and made of plastic, provided at one end with
a case head 102 inside which the primers 103 for the ignition of the propellant powders
are housed.
[0013] Preferably, in the case head 102 an annular reinforcement or base wad 106 is inserted,
which realises the mechanical junction between case head 102 and casing 101 and constitutes
a cavity for housing the propellant powder 105.
[0014] The casing 101, the case head 102 and the primers 103 constitute the case, suitable
to contain the loading elements.
[0015] The cartridge 100 thus comprises the case inside of which are housed the projectile
104 (such as a bullet or a plurality of shot pellets), the propellant powder 105 (or
gunpowder) and the wad 10.
[0016] Preferably, the cartridge 100 is of the shot pellet type.
[0017] With the percussion of the primers 103, a dart of fire is caused that ignites the
propellant powder 105, which, burning, produces gas at high pressure which presses
the projectile 104, causing it to exit the case from the opposite end with respect
to the case head 102, at an accelerating speed in the shotgun barrel.
[0018] The wad 10 serves as an elastic gasket seal with respect to the explosion gases that
develop at the moment of firing and therefore must meet the requirements of compactness
and impermeability to gases, deformability, elasticity, light weight and minimal friction
against the walls of the bore of the barrel.
[0019] With reference to the accompanying figures, and in particular to Figures 5 to 12,
various embodiment variants are shown of wad 10 according to this invention.
[0020] The wad 10 comprises a lower portion 11 in contact with the propellant powder 105,
an upper portion 13 in contact with the projectile 104, and an intermediate portion
12, arranged to join the lower portion 11 and upper portion 13.
[0021] Preferably, the lower portion 11, the upper portion 13 and the intermediate portion
12 constitute a single body. That is to say, the wad is made in one piece.
[0022] The lower portion 11 comprises a bottom wall 111, for example concave, beneath which
is located the propellant powder 105.
[0023] Preferably, the lower portion 11 comprises a cavity 113 suitable to accommodate,
at least partially, the propellant powder 105 inside it.
[0024] Preferably, the outer contour of the lower portion 11 includes a first profile 112,
substantially cylindrical, and a sloping profile 114.
[0025] In the embodiment variant of Figure 3, the first profile 112 has a smaller external
diameter with respect to the internal diameter of the casing 101 in such a way that,
once the wad 10 is inserted (as shown in Figure 1), between the casing 101 and the
profile 112 there is formed a chamber 115 suitable to receive, at least partially,
the propellant powder 105.
[0026] In the embodiment variant of Figure 3, the sloping profile 114 is inclined outwardly
in such a way that, once the wad 10 is inserted (as shown in Figure 1), between the
casing 101 and the profile 114 a chamber 115 is formed suitable to receive, at least
partially, the propellant powder 105.
[0027] Preferably, the sloping profile 114 terminates with an edge 117 having an external
diameter corresponding to the internal diameter of the casing 101 in such a way that,
once the wad 10 is inserted (as shown in Figure 1), the propellant powder 105 is confined
below it.
[0028] In the embodiment variant of Figure 5, the first profile 112 has an external diameter
corresponding to the internal diameter of the casing 101 in such a way that, once
the wad 10 is inserted (as shown in Figure 2), the propellant powder 105 is confined
below it.
[0029] In the embodiment variant of Figure 5, the sloping profile 114 is inclined internally
in such a way that, once the wad 10 is inserted (as shown in Figure 2), between the
casing 101 and the profile 114 a chamber 125 is formed suitable to receive the combustion
gas.
[0030] As shown in Figures 1 and 2, once the wad 10 is inserted in the casing 101 of the
cartridge 100, the propellant powder 105 is confined in correspondence of and/or below
the lower portion 11. In particular, in the variant of Figure 2, the propellant powder
105 is completely confined below the bottom portion 11. In the variant of Figure 1,
the propellant powder 105 is also housed in a chamber 115.
[0031] The intermediate portion 12 comprises a damper device 121, or springing device, suitable
to protect the projectile (and in particular the column of shot pellets) from the
violent shock caused by the explosion of the propellant powder 105 and reduce the
annoyance due to the recoil of the weapon when fired.
[0032] Preferably, the springing device 121 is an internally hollow cylinder, and therefore
the damping function is obtained with the cushion of air inside it. In a variant,
the springing device 121 is in the form of a honeycomb or bellows.
[0033] Preferably, the intermediate portion 12 has a smaller external diameter with respect
to the internal diameter of the casing 101 in such a way that, once the wad 10 is
inserted (as shown in Figures 1 and 2), between the casing 101 and the intermediate
portion 12 there is formed a chamber 115 suitable to receive the combustion gas.
[0034] The upper portion 13 includes an upper wall 131 against which rests the projectile
104, for example, the column of shot pellets.
[0035] The upper portion 13 has an external diameter corresponding to the internal diameter
of the casing 101 in such a way that, once the wad 10 is inserted (as shown in Figure
2), the combustion gas is confined below it.
[0036] The wad 10 comprises at least one sealing element 20 suitable to form a seal of the
combustion gases, so as to transmit the thrust generated by the propellant powder
105 to the projectile 104 in an optimal way. Advantageously, the sealing element 20,
under the thrust of the pressure generated by the combustion of the gunpowder, tends
to enlarge, preventing the release of the pressure itself.
[0037] Preferably, the wad 10 comprises a sealing element 20 in correspondence of the upper
portion 13, suitable to confine the combustion gases inside the chamber 125. This
constructive choice prevents the excessive compression of the gunpowder that, as shown
in Figure 1 is free to also occupy the chamber 115 and is better aerated. In addition,
this constructive choice allows a first venting of the combustion gases in the chamber
125, thus leaving the gunpowder more time and more space to develop further combustion
gases.
[0038] Advantageously, the wad 10 comprises a further sealing element 20 in correspondence
of the lower portion 11, suitable to confine the combustion gas below the wad 10.
[0039] In particular, in the variant of Figure 3, the wad comprises only one sealing element
20, in correspondence of the upper portion 13. In the variant of Figure 5, the wad
comprises two sealing elements 20, one in correspondence of the upper portion 13 and
one in correspondence with the lower portion 11.
[0040] Preferably, the sealing element 20 is an elastic annular lip, suitable to expand
radially in the firing step due to the pressure of the combustion gas, so as to abut
against the inner walls of the casing 101 of the cartridge 100 to form the seal against
the exist of the combustion gases.
[0041] In particular, the annular lip is oriented in the direction of the lower portion
11 of the wad 10, which is to say in the direction of the propellant powder 105.
[0042] Preferably, the annular lip has a decreasing thickness in the direction of the lower
portion 11 of the wad 10, which is to say in the direction of the propellant powder
105.
[0043] In the embodiment variants shown in Figures 7 to 12, the wad comprises, above the
upper portion 11, a container 30 suitable to contain the projectile 104, and in particular
the column of shot pellets. The container 30 is preferably a thin-walled cylinder.
Advantageously, the container 30 prevents the shot from rubbing against the walls
of the barrel, in this way limiting the deformation. Moreover, the presence of the
container 30 improves the distribution of the burst pattern, which is more concentrated,
and reduces the dispersion of the shot outside of the shotgun barrel.
[0044] Advantageously, the wad 10 with the container 30 (as realised in Figures 7, 9, 10,
11 and 12) allows obtaining a cartridge 100 particularly suitable for all sports shooting
disciplines (such as the Trap, Double Trap and Skeet) and for hunting, which assumes
long-distance shots with large and burst pattern.
[0045] In the embodiment variant shown in Figure 8, the container 30 comprises a plurality
of yielding elements 32, suitable to create breaking points in the thin walls of the
container 30.
[0046] Preferably, the container 30 comprises at least two, preferably four, yielding elements
32, uniformly distributed along the circumference of the container 30.
[0047] The yielding elements 32 are placed at least in correspondence of the upper portion
of the container 30 and develop in the longitudinal direction with respect to the
wad 10.
[0048] Preferably, the yielding elements 32 are notches, grooves, weakenings, through-holes
or slits.
[0049] Advantageously, the presence of the yielding elements 32 allows the container 30
to open just outside of the shotgun barrel so as to disperse the shot outwards and
enlarge the burst pattern within a short distance. Advantageously, the wad 10 with
the container 30 with yielding elements (as in Figure 8) allows obtaining a cartridge
100 particularly suitable for hunting, which assumes short-distance shots and very
brief shots (such as for hunting woodcock in the woods).
[0050] Advantageously, the wad 10 is made of paper. This choice allows obtaining a wad completely
biodegradable and environmentally friendly.
[0051] Advantageously, the wad 10 is made of paper by industrial moulding. This choice allows
obtaining a wad 10 that is accurate, smooth and precise in the predefined dimensions,
minimising pressure waste and speed differences between one finished cartridge and
the other, in the same loading batch.
[0052] The purpose of this invention is also a cartridge 100 provided with steel shot and
paper wad 10, as described above and shown in Figures 3 to 12. A cartridge 100 thus
produced is environmentally friendly and provides excellent shooting performance.
[0053] Note that the paper wad 10, as described above, is also usable with a cartridge 100
provided with shot made of lead or any other material. A cartridge 100 thus obtained
is more environmentally friendly than a conventional cartridge with plastic wad and
provides better shooting performance than a cartridge with felt wad.
[0054] Innovatively, a wad according to this invention is completely environmentally friendly
and provides excellent shooting performance.
[0055] Advantageously, a cartridge provided with a wad according to this invention is environmentally
friendly and performing.
[0056] It is clear that one skilled in the art may make changes to the product described
above, all contained within the scope of protection defined by the following claims.
1. Wad (10) for cartridges, comprising:
- a lower portion (11), suitable to rest on the propellant powder of the cartridge;
- an upper portion (13), on which the bullet of the cartridge is rested;
- an intermediate portion (12), arranged to join the lower portion (11) and the upper
portion (13);
- at least one sealing element (20), suitable to form a seal against the escape of
combustion gases generated by the propellant powder;
wherein the sealing element (20) is at the upper portion (13).
2. Wad (10) for cartridges, according to claim 1, wherein the sealing element (20) is
an annular lip suitable to expand radially under the effect of the pressure of the
combustion gases.
3. Wad (10) for cartridges, according to claim 1 or 2, wherein the outer contour of the
lower portion (11) comprises:
- a first profile (112), substantially cylindrical, with a smaller outer diameter
than the inner diameter of the cartridge; and
- an externally sloping profile (114) ending with an edge (117) having an outer diameter
corresponding to the inner diameter of the cartridge.
4. Wad (10) for cartridges, according to claim 1 comprising an additional sealing element
(20) at the lower portion (11).
5. Wad (10) for cartridges, according to claim 4, wherein the outer contour of the lower
portion (11) comprises:
- a first profile (112), substantially cylindrical, having an outer diameter corresponding
to the inner diameter of the cartridge; and
- an internally sloping profile (114).
6. Wad (10) for cartridges according to any of the previous claims, wherein the intermediate
portion (12) comprises a damper device (121).
7. Wad (10) for cartridges, according to any of the previous claims, comprising, above
the upper portion (11), a container (30) suitable to contain the bullet of the cartridge.
8. Wad (10) for cartridges, according to claim 7, wherein the container (30) comprises
a plurality of yielding elements (32), such as notches or grooves or weakenings or
through holes or slits, suitable to make breakpoints in the walls of the container
(30).
9. Wad (10) for cartridges, according to any of the previous claims, made of paper, preferably
by means of industrial moulding.
10. Cartridge (100), in particular for a shotgun, comprising:
- a casing (101) closed at one end by a case head (102) inside which the primers are
housed (103) to ignite the propellant powders;
- propellant powders (105), placed over the case head (102);
- a wad (10), according to any of the preceding claims, placed over the propellant
powders (105);
- a projectile (104), such as a bullet or a plurality of shot, placed over the wad
(10).