U.S. patent number 3,840,232 [Application Number 05/325,067] was granted by the patent office on 1974-10-08 for frangible flying target.
This patent grant is currently assigned to Southwest Research Institute. Invention is credited to John M. Dale, Allen C. Ludwig.
United States Patent |
3,840,232 |
Ludwig , et al. |
October 8, 1974 |
FRANGIBLE FLYING TARGET
Abstract
A frangible flying target or clay pigeon molded from a
composition comprising from about 35 percent to about 70 percent by
weight of elemental sulphur mixed with about 30 percent to about 65
percent of an inert filler such as limestone dust. The composition
is first heated to produce a fluid mix and is then cast or molded
to produce a target of desired dimension and configuration. By the
inclusion of materials that are dimensionally unstable in the
presence of water, such as bentonite clay, it is possible to
produce an environmentally degradable target.
Inventors: |
Ludwig; Allen C. (San Antonio,
TX), Dale; John M. (San Antonio, TX) |
Assignee: |
Southwest Research Institute
(San Antonio, TX)
|
Family
ID: |
23266294 |
Appl.
No.: |
05/325,067 |
Filed: |
January 19, 1973 |
Current U.S.
Class: |
273/362;
106/287.32 |
Current CPC
Class: |
F41J
1/01 (20130101) |
Current International
Class: |
F41J
1/00 (20060101); F41J 1/01 (20060101); F41j
001/00 () |
Field of
Search: |
;273/105.4
;106/287SC |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Oechsle; Anton O.
Assistant Examiner: Siskin; Marvin
Attorney, Agent or Firm: Lee; Ted D. Comuzzi; Donald R.
Claims
Now having described a preferred embodiment of my invention, what I
claim is:
1. A frangible flying target consisting of 35 percent to 70 percent
by weight of an elemental sulfur composition and from 65 percent to
30 percent by weight of a finely divided inert filler material
consisting of limestone dust, said frangible flying target being
shatterable upon impact by a single pellet.
2. The frangible flying target of claim 1 wherein the finely
divided inert filler material includes from 1 percent to 10 percent
by weight of a material that is dimensionally unstable in the
presence of water.
3. The frangible flying target of claim 2 wherein the inert filler
material consists of limestone dust and from 1 percent to 10
percent by weight of the limestone dust of bentonite clay.
Description
BACKGROUND OF THE INVENTION
This invention relates to improvements in composition targets
sometimes known as clay pigeons which are suitable for use in trap
and skeet shooting. The targets are usually in the form of a saucer
shaped structure molded from some suitable mixture generally
consisting of petroleum pitch or some other binder and a filler
material such as clay or some other finely divided mineral to
provide a relatively fragile structure. The targets are designed to
be nested for packing purposes and must be strong enough to
withstand the rigors of commercial handling and shipping.
These targets or "clay pigeons" are intended for use by marksmen
and must be capable to being projected into the air a considerable
distance, usually with a mechanical throwing apparatus known as a
trap. The use of such artificial targets and mechanical throwing
devices by marksmen grew out of the dwindling supply of live birds
as well as the concern to preserve our wildlife and has gained in
popularity each year.
Several types of traps are used for projecting the targets. All of
these provide a means to engage the target and project it with
considerable speed into the air. It is a requirement that the
target have sufficient "trapping strength" to withstand the
throwing force of the trap, otherwise, the target will break in the
trap.
Since the primary purpose of trap shooting is to demonstrate the
markmanship of the shooter, it is necessary that the targets be
designed to indicate when the marksman has scored a hit. If the
composition of the target is such that a pellet will merely chip a
fragment off the target, then the chip will be so small that it is
not clearly visible and the shot will not be scored as a hit.
Likewise, a pellet that hits a target and passes through it,
leaving a small hole will not be scored as a hit since it is not
visible. Since it is impractical to retrieve the targets once they
have landed, the best method of indicating a hit is to make the
target fragible so that it will shatter upon impact from a single
pellet.
Furthermore, since trap shooting takes place in the out of doors,
and since the targets are generally shattered by the marksman and
fall to the earth, they are susceptible to being eaten by birds and
other wild animals. It is therefore desirable that the composition
of the targets be completely nontoxic to birds and wild animals as
well as to plant life. Trap shooting is conducted in various kinds
of weather conditions and at all hours of the day or night.
Therefore, the color of the target is very important and the
necessity to provide a variety of colors for varying weather
conditions is apparent. Colors may also be used to impart more
realism to the shooting by simulating the colors of various birds,
or provide the maximum amount of contrast between the target and
the background.
Since by their very nature targets are totally expendable in use,
it is also important that they be constructed of materials having
very nominal cost.
In the past, targets have been constructed of various materials and
with varying physical configurations. Glass balls have been used
and traps were designed to accomodate these targets. Various types
of cylindrical targets have been designed and traps for projecting
the cylindrical targets have been in use for many years.
There has been a constant guest for newer and better targets at
lower cost. While only slight changes have been made to the
geometrical configuration of the targets in recent years, the
material composition has undergone numerous changes in an attempt
to improve target performance and quality. Material composition of
the targets has included finely ground clay mixed with water,
molded and kiln dried. These clay targets were generally quite hard
and it was often very difficult to break or even chip one. Many
other materials such as plaster of Paris, sand and pitch have been
used, however, these have all suffered from deficiencies in one or
more of the desired characteristics of a good target. Some break
well in cold weather but very poorly in warm weather, and vice
versa. More recently, composition materials have become popular in
the manufacturing of targets because they afford an opportunity to
select desirable qualities from various materials that are used.
After several decades of experimentation and innovation in the size
and configuration of targets, they have now for the most part been
standardized with generally a saucer shaped design and a weight on
the order of 3 oz. and a diameter of 4 1/4 inches. The material
content of the targets vary among manufacturers but the finished
target must be strong enough to withstand the rigors of commercial
shipping and the stresses and shocks of the throwing trap and at
the same time be sufficiently fragile to be shattered when impacted
with only one No. 9 pellet. Furthermore, the cost of the target,
its color characteristics and its toxic effect on plant and animal
life are also important considerations.
The composition targets and the clay targets which have heretofore
been used have been deficient in many respects. As noted
previously, the clay target is very hard and difficult to break.
The most popular composition target presently in use is a target
consisting of a composition of ground limestone and pitch such as
those disclosed in U.S. Pat. No. 2,831,778 and U.S. Pat. No.
3,399,255. The compositions disclosed in these patents and the
method of manufacture render the cost of such targets relatively
expensive. Furthermore, the targets are toxic to a degree and
painting of the target is usually required in order to obtain a
satisfactory color since the use of pitch results in a very dark
colored target. Furthermore, since pitch is very susceptible to
changes in temperature, the targets do not shatter with consistency
over a wide range of temperatures. Pitch is also in short supply
and therefore expensive. Composition targets presently in use are
not environmentally degradable and therefore cause concern to the
ecology minded because the discarded and/or shattered targets
clutter the countryside and may be eaten by animals causing
sickness or even death.
It is a primary object of this invention to provide a target for
use in trap shooting that is economical to manufacture, that is
made from materials which are readily and abundantly available and
which meets the standard specifications which have been established
in the industry.
It is a further object of this invention to provide a target that
has the strength to withstand the rigors of shipping and the stress
of the trap but which will shatter upon impact of a single pellet.
It is also an object of the invention to provide a target that is
capable of being produced in a variety of colors for use in varying
conditions of visibility and to provide more realism for the
shooter. It is also an object to provide a target that is non-toxic
to both plant and animal life and which is environmentally
degradable.
The present invention relates to targets molded from a composition
containing elemental sulphur. Elemental sulphur has many known uses
and applications, there being over 7 million tons of it produced in
the United States each year. In many areas of use it has been
desirable and even necessary to chemically modify the sulphur to
employ it in certain applications. We have discovered that
compositions of elemental sulphur and certain other readily
available materials have outstanding characteristics for use as
targets for skeet and trap shooting with or without the necessity
of chemically modifying the sulphur.
In laboratory tests, elemental sulphur was mixed with 30 percent to
65 percent by weight of limestone dust and the mixture was heated
to produce a liquid mixture which was then poured into a two-part
commercial target mold. Solidification of the material in the mold
was very rapid and resulted in targets having outstanding
appearance and characteristics. For example, a composition of 70
percent sulphur and 30 percent limestone weighed only 10 percent
more than the generally accepted commercial standard weight for
such targets, yet it was 43 percent stronger when subjected to a
standard tensile strength test which is accomplished by placing the
throwing ring of the target in compression. The target when
subjected to a shatter test was much more fragile than the standard
composition target and easily shattered with the impact of a single
pellet. As the percentage of sulphur was decreased with a
proportionate increase in limestone the target strength increased
substantially. For example, with a composition of 50 percent
sulphur to 50 percent limestone, the target weight was increased to
23 percent above the generally accepted standard commercial target
weight but the target tensile strength had increased to 86 percent
greater than a standard commercial target. In all cases, the target
containing a portion of sulphur shattered more readily than did the
standard commercial limestone-pitch composition target. With a
composition consisting of a mix of 35 percent sulphur and 65
percent limestone, the liquid mixture becomes very stiff and it is
then necessary to use hydraulically pressed forms. However, the
targets produced thereby have good strength. Since the strength of
the target increases at a faster rate than the weight increases
when the proportion of limestone is increased, a target having
thinner walls may be cast while maintaining the outside dimensions
and weight to the generally accepted standard specifications. This,
of course, would produce a target containing less materials by
volume but with greater tensile strength and better shattering
characteristics. As the sulphur content of the targets was
increased above 70 percent sulphur by weight, the strength
characteristics decreased to less than the standard pitch-limestone
composition target and the 100 percent sulphur target does not
extract well from the mold.
For an environmentally degradable target, a composition of the type
described containing elemental sulphur and limestone with the
addition of a material which is dimensionally unstable in the
presence of water such as bentonite clay in an amount of 1 - 10
percent by weight of the limestone may be added. A target comprised
of this composition when wetted will decompose into a very fine
dust. It has been found that the tensile strength of the target is
not appreciably affected by the addition of the bentonite clay.
The targets manufactured from the sulphur-limestone composition can
be colored with the use of pigments which blend readily with the
sulphur to produce any desired color. This, of course, eliminates
the need for painting the target after it has been removed from the
mold, which, of course, is necessary when pitch is used as the
binder. The sulphur-limestone composition is non-toxic to both
plant and animal life when fragments are scattered over the
shooting area and animals may eat the sulphur without any ill
effects. The targets produced from the limestone-sulphur
composition produce no obnoxious odors.
Elemental sulphur is readily available in large quantities at very
low cost. Pitch, which is the most widely used binding material
presently employed in the manufacture of targets, is coming in
short supply. It is very expensive and the cost is increasing. Its
use as a binder for limestone or other filler materials in the
production of targets, while having characteristics superior to
other known binders on the market today, has many undesirable
features as discussed previously. Elemental sulphur has been found
to be a very suitable and desirable binder for use with a limestone
filler material. It should also be noted that sulphur is adaptable
for use as a binder with filler materials such as talc, sand or
soil, however, limestone has been found to have certain desirable
characteristics and has been used in the preferred embodiment.
* * * * *