Shooting range target

A self-sealing target for firearm projectiles includes a body of an ionomeric polymer. A preferred polymer is a metallic salt of a copolymer of ethylene and a vinyl monomer having an acidic group.

FIELD OF THE INVENTION 
This invention relates generally to target shooting. More particularly, the 
invention relates to target structures for shooting ranges. 
BACKGROUND OF THE INVENTION 
Target shooting is a widespread activity, both for purposes of recreation 
and in connection with the training of law enforcement officers, military 
personnel and individuals interested in personal self-defense. Target 
ranges provide a safe and controlled environment for year-around shooting. 
Furthermore, target ranges minimize the impact of noise and the hazards of 
stray projectiles on the surrounding environment; hence, they are of 
increasing popularity in urban areas. 
Targets generally used at shooting ranges are of a solid, bullet penetrable 
material used typically to support a removable paper target thereon with 
appropriate indicia such as the well known circular "bulls-eye" target. 
Other target structures often used for military or police training 
applications may take specific shapes or silhouettes and may also have 
indicia or aiming points thereon. Many such target structures are 
incorporated into mechanical systems which cause them to "pop-up" for the 
shooter to shoot at. The mechanical system may also cause the targets to 
fall down when the appropriate aiming point is hit. 
In any target range, and in an indoor range in particular, it is necessary 
to provide a target structure which will allow projectiles to penetrate 
the target and pass into a bullet trapping structure without damage or 
hazard from ricochets or bullet fragments. By the same token, it is 
desirable to have a target structure which can withstand a large number of 
bullet penetrations while substantially maintaining the target integrity, 
thus allowing the target to be used on a continued and repeated basis for 
a substantially longer period of time without the need for replacement. 
Wood, cardboard, fiberboard and other rigid penetrable structures have long 
been employed in shooting ranges to serve as targets. Each penetration 
through such targets results in the removal of a portion of the target 
material and creates a corresponding hole in the target, hence these 
target structures quickly lose their integrity and consequently their 
ability to function as a target. Polyethylene structures have also been 
used as targets and provide improved performance over wood and other 
materials. However, each penetration still removes material from the 
structure, resulting in the need for target replacement after repeated 
penetrations. 
It will be appreciated from the foregoing that there is a need for an 
improved target structure which will allow repeated bullet penetrations 
without sustaining substantial damage and loss of integrity. The present 
invention addresses this need by providing a self healing target structure 
which effectively allows penetration by a variety of calibers and loads, 
without any significant loss of the target material and without 
significant damage to the structure. These and other advantages of the 
present invention will be readily apparent to those of skill in the art 
from the drawings, discussion and description which follow. 
BRIEF DESCRIPTION OF THE INVENTION 
There is disclosed herein a target structure for firearm projectiles. The 
structure is composed of an ionomer of the type comprising a metallic salt 
of a copolymer of ethylene and a vinyl monomer having an acidic group. It 
has been found, in accord with the principles of the present invention, 
that this ionomeric material is very effective at slowing and absorbing 
the impact from bullets, and that a bullet penetrating the material will 
initially stretch the material and form an opening which is self healing 
in that it reseals itself after the bullet has passed. The ionomeric body 
may be made in any appropriate shape or form with appropriate target 
indicia thereon or it may simply be employed to support a paper or other 
disposable target thereon. The ionomeric material may also be used to 
cover exposed target stand structures to absorb bullet impact and prevent 
fragment splatter by absorbing bullet fragments caused by impact with the 
target stand. 
In one particular embodiment, the ionomer comprises a sodium or zinc salt 
of a copolymer of ethylene and methacrylic acid. In some instances the 
ionomeric material may further include a layer of aramide polymer 
laminated thereto.

DETAILED DESCRIPTION OF THE INVENTION 
FIG. 1 illustrates a shooting range target 10 structured in accord with the 
principles of the present invention as will be more fully described 
hereinbelow. Also shown in FIG. 1 is a shooter 12 shooting a firearm 22 at 
the target. Referring now to FIG. 2, there is shown a top plan view of a 
shooting range which includes a target 10 structured in accord with the 
principles of the present invention. Also shown in FIG. 2 is a firearm 20 
and projectile 22 fired from the firearm. The target 10 is fabricated from 
a type of polymer referred to as an ionomer. This material comprises a 
metallic salt of a copolymer of an olefin such as ethylene and a vinyl 
monomer having an acidic grouping thereon. In an ionomer, linkage of the 
polymeric chain is accomplished by ionic as well as covalent bonds. It has 
been found, in accord with the principles of the present invention, that 
ionomeric polymers are very effective at absorbing the kinetic energy of 
bullets. It has been found that a bullet passing through a sheet of 
ionomeric polymer will initially stretch the material and form an opening 
which reseals itself after the bullet has passed. 
One ionomeric polymer having particular utility in the present invention is 
the sodium or zinc salt of a copolymer of ethylene and methacrylic acid. 
Materials of this type are available under the designation Surlyn.RTM. 
from the DuPont Corporation. The material sold under the grade designation 
8940 has been found to be particularly advantageous for fabricating 
targets. This material includes the sodium cation and it has a nominal 
density of 0.95 g/cm.sup.3 ; a melt flow index of 2.8 g/10 minutes per 
ASTM D-1238; a notched izod toughness of 1025 J/cm per ASTM D-256; a 
tensile impact of 1020 kJ/m.sup.2 at 20.degree. and 760 kJ/m.sup.2 at 
-40.degree. C. per ASTM D-1822s; it has a flexural modulus of 350 MPa at 
23.degree. C. per ASTM D-790; a tensile of strength 33.1 MPa, a yield 
strength of 15.9 MPa and an elongation of 470% all per ASTM D-638. Its 
shore D hardness is 65 per ASTM D-2240. The melting point of this polymer 
per data analysis is approximately 81.degree.-96.degree. C. and its 
freezing point is approximately 51.degree.-80.degree.. 
Other grades of Surlyn.RTM. polymer, particularly grade 8920 have generally 
similar properties and are also usable in the practice of the present 
invention. In those instances where low temperature conditions are 
encountered, as for example in outdoor ranges, materials with better low 
temperature properties, such as Surlyn.RTM. 8020, may be employed. It is 
to be understood that other ionomeric polymers, particularly those having 
properties similar to those herein described may also be employed in the 
practice of the present invention. In some instances the ionomeric 
material may be further modified by the inclusion of fire retardant 
agents, coloring agents and the like. The ionomeric material may also 
include a fabric layer laminated thereto to facilitate the painting of 
appropriate target indicia thereon. One fabric having particular utility 
in this regard is comprised of a ,polyester nonwoven fabric available 
under the trade name Reemay.RTM. by DuPont. The fabric is preferably 
extrusion laminated onto the surface of the ionomeric material. 
In the illustrated embodiment the shooter 12 is firing a firearm 20 at 
target 10. As the bullet 22 penetrates the target a hole is created in the 
target 10 which reseals once the penetration is complete. The bullet 22 is 
then stopped by a backstop. 
Target 10 may include a steel fabricated target support structure or stand 
and may also employ mechanical systems which move the target up and down 
to simulate a object popping up and down from behind cover. The cover may 
also be fabricated from a steel plate. One or more sheets of ionomeric 
material may be used to cover or clad the target support structure and/or 
steel plate to prevent dangerous bullet fragments from ricocheting and 
striking shooter or bystanders. As bullet 22 penetrates the ionomeric 
material striking the target support structure or steel plate, resulting 
bullet fragments are absorbed by the ionomer and prevented from 
splattering. As bullet 22 penetrates or misses the target, target 10 may 
itself also act as a splatter preventing curtain preventing dangerous 
bullet fragments and dust resulting from impact on a backstop from 
reaching the shooter. The ionomeric material may also be used as a 
non-target curtain placed between the target and the backstop in order to 
prevent splattering. 
The backstop may also be constructed of an ionomeric polymer and may 
comprise a plurality of separate sheets of ionomeric material as disclosed 
in U.S. patent application Ser. No. 08/040,140, filed Mar. 20, 1992, 
entitled "Shooting Range Backstop." 
Preferably the thickness of target 10 ranges from 0.125 inches to 
approximately 0.500 inches. In a series of practical test employing 
Surlyn.RTM. 8940 of 0.250 inch thickness, it was found that a 0.380 
caliber jacketed solid-point bullet fired at 90.degree. to an array of 
0.250 inch sheets would pass through two sheets and be stopped by a third. 
Under the same conditions, in a 9 mm jacketed solid-point bullet required 
six 0.250 inch sheets to stop it. When the 9 mm bullet was fired at a 
45.degree. angle to the sheets, it was stopped by the fourth. 
It will be appreciated from the foregoing that a highly efficient target 
for firearm projectiles may be fabricated by employing a body of ionomeric 
material as a penetrable bullet slowing member. The target may employ an 
ionomeric member of a desired size and shape and may have desired target 
indicia or aim points painted thereon. The ionomeric material may also be 
vacuum formed into a three dimensional structure of a particular desired 
size and shape such as a humanoid shape for use in military or police 
training application. The target structure may also be employed as part of 
a pop-up type target system in which a mechanical system raises and lowers 
the target, and in some instances scores hits. The target may also simply 
serve as a support structure for a paper or other disposable target 
attached thereto. Therefore, it is to be understood that the invention may 
be practiced in particular forms which differ from the ones disclosed 
herein. The drawings, discussion, description and example set forth herein 
are merely meant to illustrate particular embodiments of the invention and 
are not meant to be limitations on the practice thereof. It is the claims, 
including all equivalents, which define the scope of the invention.