The field of the invention is projectiles for use in cartridges fired from handguns and other firearms.
Projectiles, or bullets, are made in a variety of shapes and sizes depending upon their intended use. The shape and size of a projectile affects the kinetic energy that is transferred to a target upon impact. The kinetic energy of a discharged projectile will be a function of its mass and its velocity via the well-known formula Kinetic Entergy (KE)=½ (mass)(velocity)(velocity). Often, as is the case in hunting, it is desirable to maximize the kinetic energy transferred by the projectile, thus increasing its lethality.
Most projectiles that are designed to maximize lethality suffer from various shortcomings. Expanding projectiles and fragmenting projectiles, for example, succeed in causing an increased amount of damage to a target, compared to the average projectile. However, expanding and fragmenting projectiles frequently transfer an inadequate amount of energy to the target. Further, expanding and fragmenting projectiles are generally difficult to control and, thus, produce inconsistent results.
Projectiles that are designed to tumble typically transfer a higher amount of kinetic energy than those previously discussed. A problem observed with prior art designs for tumbling projectiles is the inability to control how and when the projectile tumbles.
The present invention comprises designs for a projectile, or bullet, which tumbles upon impact with a target. The design of the projectile may be tailored to the specification of the shooter or designer for a specific target so as to create an optimal energy release at an optimal depth in the target, thus increasing the efficiency. The projectile is generally made of copper or similar material. However, any type of metal, composite, or combination thereof may be used.
The tumbling of the projectile 100 may be controlled by changing the length of the first portion side 109 from the trailing end 107 to the point 105. Increasing such length causes the projectile 100 to begin to tumble very close to or at the target. Decreasing such length causes the projectile 100 to begin to tumble farther from the point of impact. The tumbling of the projectile 100 may also be controlled by flattening the point 105 so that there is a flat surface (not shown) at the leading end or point 105 of the projectile 100. Increasing the diameter of such flat surface causes the projectile to begin to tumble farther from the target, whereas decreasing the diameter of such flat surface causes the projectile to begin to tumble close to or at the target.
The projectile 500 has a first portion 502, a first portion side 503, a base 504, a mid-portion 506, a first portion trailing end 507, a pointed tip 510 at a leading end of the projectile 500, a tip side 520, and a tip trailing end 530. The first portion trailing end 507 and the tip trailing end 530 may not be two specific surfaces or disconnected from the part from which they extend. The first portion trailing end 507 and the tip trailing end 530 may just designate the location along the length of the projectile 500 where the diameter of the projectile 500 begins to decrease, thus tapering the projectile 500 in the direction of its leading end. It will be noted that the first portion side 503 forms an acute angle with the first portion trailing end 507, and that the tip side 520 forms a second more acute angle with the tip trailing end 530. The addition of the tip 510 and its second, more acute (sharper) angle with respect to the tip trailing end 530 (and also more acute than the angle between the first portion side 503 and the first portion trailing end 507) causes the projectile 500 to tumble after it impacts a target.
When a projectile impacts a target it releases energy which can be observed as a cavitation in ballistic gel. The cavitation in ballistic gel represents damage that would be caused to the tissue if the projectile 100 or 500 impacted a living target. As the projectile 100 or 500 begins to tumble, an increased amount of energy is released. The design of the projectile 500 may be tailored to the specification of the shooter or designer. The specifications that may be changed to affect the performance of the projectile (i.e. larger cavitation) include a sharper or more acute angle between the tip side 520 and the trailing end 530 of the tip 510, the radius of the first portion 502, the diameter of the point of the nose, the width or diameter of the mid-portion 506, the speed of the projectile 500 when fired from the firearm, and the width or diameter of the base 504. It was found that, if the more acute (sharper) angle between the tip side 520 and the tip trailing end 530 is placed at the forward end of the projectile, as shown in projectile 500, the projectile will tumble early and continue to tumble through the target. If the length of the first portion side 503 is increased the projectile will tumble, and the tumbling of the projectile 500 will increased in frequency as the length of the first portion 503 is increased. However, as the length of the first portion side 503 is decreased, the projectile is less likely to tumble, and further shortening the first portion side 503 can prevent the projectile from tumbling at all. It should also be noted that by changing certain aspects of the design, such as length of the tip, for example, performance may be affected in ways other than just tumbling. For example, the yaw or roll of the bullet may be affected by such changes.
The table below summarizes the measurements of the motion of the projectiles discussed in
The data shown in the table above demonstrates the benefits of the present invention. Compared to the projectile in
This application claim priority to U.S. Provisional Application Ser. No. 61/931,362, filed Jan. 24, 2014, the disclosure of which is incorporated herein by reference.
Number | Date | Country | |
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61931362 | Jan 2014 | US |