US3672304A

US3672304A - Special purpose firearms projectile

Info

Publication number: US3672304A
Application number: US23825A
Authority: US
Inventors: Patrick F Rogers; Warren L Hendrickson
Original assignee: Lockheed Aircraft Corp
Current assignee: Lockheed Martin Corp
Priority date: 1970-03-30
Filing date: 1970-03-30
Publication date: 1972-06-27
Anticipated expiration: 1989-06-27

Abstract

A small arms bullet with controlled flight characteristics fireable at high velocities from conventional small arms. The bullet has a projecting spike tip forming a supersonic shock wave cone. The bullet travels inside this shock wave cone and has low aerodynamic drag at supersonic velocities. The bullet is light weight and has a blunt drag face providing a high aerodynamic drag configuration for the bullet at subsonic flight velocities to rapidly decelerate the bullet after a preselected initial combat range, thereby reducing its long range danger to bystanders and property. Within the preselected combat range the shape and velocity characteristics of the bullet provide high ''''stopping power'''' yet a reduced lethality.

Description

United States Patent Rogers et al.

[541 SPECIAL PURPOSE FIREARMS PROJECTILE [72] Inventors: Patrick F. Rogers, Cupertino; Warren L.

Hendrickson, San Jose, both of Calif.

Lockheed Aircraft Corporation, Burbank, Calif.

[22] Filed: March 30, 1970 [21] Appl.No.: 23,825

[73] Assignee:

[15] 3,672,304 1 June 27, 1972 3 ,050,000 8/1962 Katsanis 102/105 3,107,619 10/1963 Daniels ...l02/105 3,267,857 7/1966 Lindberg, Jr. 102/105 Primary Examiner-Robert F. Stahl Attorney-Paul F. Morgan and George C. Sullivan [57] ABSTRACT A small arms bullet with controlled flight characteristics fireable at high velocities from conventional small arms. The bullet has a projecting spike tip'forming a supersonic shock wave cone. The bullet travels inside this shock wave cone and has low aerodynamic drag at supersonic velocities. The bullet is light weight and has a blunt drag face providing a high aerodynamic drag configuration for the bullet at subsonic flight velocities to rapidly decelerate the bullet after a preselected initial combat range, thereby reducing its long range danger to bystanders and property. Within the preselected combat range the shape and velocity characteristics of the bullet provide high stopping power" yet a reduced lethality.

1 Claim, 5 Drawing Figures PATENTEDJUHZ'! m2 3. 672.304

FIG. 5

PATRICK F. ROGERS WARREN L.HENDR|CKSON INVENTORS.

AH ney SPECIAL PURPOSE FIREARMS PROJECTILE The present invention relates to a small arms bullet with controlled flight characteristics, and in particular to a bullet providing a higher velocity over a short preselected combat range yet a rapid reduction in velocity over a short preselected combat range yet a rapid reduction in velocity beyond said combat range by a simple fixed configuration with low supersonic aerodynamic drag and high subsonic aerodynamic drag.

The desired combat range for small arms, for example police pistols, is quite short. The generally recognized maximum effective range for hand guns is 50 yards, and fire is rarely directed beyond this range. Yet conventional bullets for such small arms have mass and sustained velocity characteristics rendering them extremely dangerous, particularly in urban areas, to innocent personnel and objects over a range extending far beyond this desired combat range. Also, conventional bullets are often unnecessarily lethal, in that the kinetic energy transfer from the bullet to the target necessary for stopping power" is largely expended internally through the target rather than rapidly transferred to the target upon impact. These same disadvantages are also present in other small arms use in urban areas for riot control and the like; e.g., shotgun slugs, rifle and light machine gun bullets.

The flight characteristics of a projectile can, of course, be changed by varying the configuration of the projectile in flight. However, this requires moving mechanisms operating in flight, as shown for example if US. Pat. Nos. 2,936,710 and 3,l57,l23. These projectiles are obviously not suitable for small arms bullets.

There is disclosed herein a special purpose bullet with controlled flight characteristics particularly suitable for small arms used in urban areas. This bullet overcomes the above stated and other disadvantages of conventional small anns bullets. Its controlled variable drag flight characteristics are provided by a simple, inexpensive, integral structure. Yet no moving parts are required during the flight of the bullet; i.e., it has a fixed flight configuration. The disclosed bullet also provides a rapid impact energy transfer to the target for good stopping power, yet provides reduced internal injuries.

Further objects, features and advantages of the invention pertain to the particular arrangement and structure whereby the above mentioned aspects of the invention are attained. The invention will be better understood by reference to the following description and to the drawings forming a part thereof, which are substantially to scale, wherein:

FIG. I is a plan view of a first exemplary bullet embodiment of the invention in flight;

FIG. 2 is a frontal view of the bullet of FIG. 1;

FIG. 3 is an axially cross-sectional view of a second bullet embodiment of the invention shown prior to firing;

FIG. 4 is a frontal view of the bullet of FIG. 3; and

FIG. 5 is a plan view of the bullet of FIGS. 3 and 4 in flight.

Referring first to FIGS. 1 and 2, there is shown therein a small arms bullet in accordance with the present invention. The bullet 10 has a generally conventional bullet body 12 adapted to be fired from conventional small arms cases through a conventional small arms barrel. The particular bullet shape illustrated is for a conventional 38 caliber police revolver. The bullet body 12 is somewhat lighter in weight than a conventional bullet of the same caliber so as to have a higher supersonic muzzle velocity than a conventional bullet.

In contrast to a conventional bullet nose, the bullet 10 has a large blunt drag face 14 at its forward end extending transverse the direction of flight of the bullet. The drag face 14 is here a flat annular shoulder area extending across the front face of the bullet with a diameter substantially that of the full (maximum) bullet diameter.

Fixed axially forward of the drag face 14 from the bullet body 12 is a central spike 16. The spike 16 may be constructed as an integral part of the body-l2 (of the same material) or it may be a separate attached member of a suitable material such as a copper pin. The spike 16 has a forward tip 18 having a much smaller elTective frontal area than the drag face 14.

For supersonic flight of the bullet 10 the spike tip 18 is adapted to form a clean low drag supersonic shock wave cone 20 (flow separation region) which has its apex at the spike tip- 18 and opens rearwardly toward the bullet body 12 about the central axis of the bullet 10. The included angle of this shock wave cone 20 is, of course, a known function of velocity, air pressure and temperature.

The spike tip 18 and the drag face 14 are positioned with respect to one another on the bullet 10 so that for supersonic flight of the bullet 10 the drag face 14 and the entire bullet body 12 is positioned entirely inside the shock wave cone 20 formed by the spike tip 18, thereby providing a low aerodynamic drag configuration for the bullet 10 at supersonic flight velocities. For this flow separation effect to be effective the ratio of the distance between the drag face 14 and the spike tip 18 to the diameter of the drag face 14 should be between 0.5 and 3.0. For example, fora pistol bullet with a muzzle velocity of 1,400 ft/sec the total included angle of the shock wave cone 20 is less than and therefor this ratio can be approximately 1.0. By this low supersonic drag configuration, the bullet 10 maintains a high supersonic flight velocity for a pre-selected initial combat range after firing.

The bullet weight and charge are selected to give a muzzle velocity such that over an initial selected combat range (e.g. 50 yards) the velocity of the bullet 10 will remain supersonic, but will have dropped to approximately the speed of sound as the bullet reaches the outer end of that range. At that point, with its velocity dropping below the speed of sound, the configuration of the bullet l0 automatically provides a radically altered aerodynamic characteristic which rapidly further decelerates the bullet by high aerodynamic drag. This high aerodynamic drag is provided by the high drag configuration of the blunt drag face 14 at subsonic flight velocities. Thereby, within a short distance beyond the'preselected combat range, the bullet 10 is slowed to a velocity at which it is of greatly reduced danger to objects and personnel. The maximum range of the bullet is also greatly reduced.

If desired, even further drag'may be provided by deliberately introducing instabilities in the flight of the bullet l0 beyond the combat range. This may be provided for example by slightly unbalancing or offsetting the position of the spike 16 with respect to the central bullet axis.

Considering the action of the bullet .10 against a target within the selected combat range, as stated above the bullet I0 is traveling at a supersonic velocity. The combination of this high velocity and the blunt face of the drag face 14 provide a high energy transfer to the target upon impact, thus providing improved stopping power. The bullet 10 has the stopping power advantages of a blunt nosed bullet without the disadvantageous flight characteristics normally associated with such bullets. Yet the light weight and blunt face of the bullet 10 reduces the penetration of the bullet into the target. Accordingly, maximum energy transfer takes place in the first 3 to 4 inches of target penetration. Further, the bullet 10 is constructed so that it does not mushroom. The combination of these features provides a bullet 10 which has a reduced likelihood of inflicting lethal wounds as compared to conventional bullets, yet without any reduction in stopping power. This may be better understood from the recognized formula for stopping power discussed in Chapter 12, Text Book of Pistols & Revolvers, Major Julian S. I-Iatcher, Ordnance Dept., US Army, Small Arms Technical Publishing Co., 1935, (see especially pages 427 435). The lower lethality potential is indicated, for example, by the text Wound Ballistics, Col. James S. Cottes, Jr., Editor in Chief, Ofiice of the Surgeon General, Department of the Army, I962, Library of Congress Card Catalogue No. 62-60002 (see especially page 225 Referring to FIG. 3 5, a second embodiment'of the invention is in the form of a chambered 22 which is illustrated therein. While the bullet 10 functions well in revolvers, the bullet 22 is preferred for magazine or belt fed weapons. For such weapons, the bullet 22 allows conventional feeding without requiring modification of the fire arm. The bullet 22 differs from the bullet 10 primarily in that it has a spike 24 which prior to firing is recessed substantially flush with the bullet nose in the interior of the bullet. Thus, until the bullet 22 is fired, its external profile is close enough to that of a conventional bullet that it can be fed and chambered in the same manner as a conventional bullet. However, when the bullet 22 is fired, as shown in FIG. 5 and the dashed outline in FIG. 3, the chamber pressure of the firearm drives the spike 24 into a fixed projecting position where it then functions in the same manner as the spike 16 of the bullet of FIG. 1 throughout the flight of the bullet 22.

The bullet 22 has a drag face 26 more rounded at its outer edges than the drag face 14 of the bullet 10 in order to allow proper magazine feeding. However, the bullet 22 has a large diameter with respect to its length and mass so as to provide a large effective drag face 26 transverse the direction of flight.

As may be seen in FIG. 3, the bullet 22 has a large recess 28 in its base or rear portion. This substantially reduces the mass of the bullet without affecting its stability and allows an increase in its supersonic muzzle velocity. The recess 28 also provides the space into which the spike 24 is retracted prior to firing of the bullet 22. The bullet 22 is shown conventionally copper or steel jacketed with a lead interior.

The spike 24 is preferably a slightly tapered pin constructed from brass or other suitable material harder than the lead interior of bullet 22. The spike 24 has an enlarged head 30 at its rearward end in the recess 28. Prior to firing the spike 24 is held by a press fit in a corresponding axial hole through the bullet 22.

Upon firing of the bullet 22, gas pressure drives the spike 24 forward through the bullet body until its enlarged head 30 engages the rearward face of the bullet interior. The head 30 of the spike 24 thereby limits the projection of the spike 24 to the desired distance of extension of the spike tip from the drag face 26, as shown by the dashed out line position of the spike 24 in FIG. 3. This projection distance is determined in the same manner as for the spike tip 18 of bullet 10. The spike 24, having been forced tightly through the hole in the lead core of bullet 22, is fixed in its extended position for the entire flight of the bullet. This is assisted by the fact that the drag forces on the body of the bullet 22 are much higher than those on the smaller diameter spike 24. Thus, the bullet 22 maintains the configuration shown on FIG. 5 throughout its flight, thereby maintaining a high supersonic flight velocity for a preselected initial combat range after firing and then rapidly decelerating thereafter by a high subsonic drag, similarily to the bullet 10.

It may be seen that there has been described herein an improved small arms bullet with novel characteristics. While the bullet described herein is presently considered to be preferred, it is contemplated that numerous further variations and modifications within the purview of those skilled in the art can be made therein. The following claims are intended to cover all such variations and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

l. A small arms bullet with controlled flight characteristics,

said bullet having:

a light weight generally cylindrical bullet body adapted to be fired from conventional small arms at a supersonic muzzle flight velocity,

a blunt forward drag face providing a high aerodynamic drag configuration for said bullet at subsonic flight velocities and rapid impact energy transfer,

said drag face being substantially flat and extending over substantially the entire frontal area of said bullet,

and a non-ablative, integral spike tip fixed forwardly of said drag face at a fixed distance in the flight of said bullet,

said spike tip having a much smaller effective frontal area than said drag face,

said spike tip being adapted to form a supersonic shock wave cone at the forward end of said bullet during the flight of said bullet, said spike tip and said drag face being positioned with respect to one another on said bullet so that for supersonic flight of said bullet said drag face is inside said shock wave cone formed by said spike tip, thereby providing a low aerodynamic drag configuration for said bullet at supersonic velocities,

whereby said bullet maintains a high supersonic flight velocity for a preselected initial combat range after firing but then rapidly decelerates due to high aerodynamic drag after the bullet slows to a subsonic flight velocity, thereby reducing said bullets danger to objects and personnel outside of said combat range and reducing said bullets range.

Claims

1. A small arms bullet with controlled flight characteristics, said bullet having: a light weight generally cylindrical bullet body adapted to be fired from conventional small arms at a supersonic muzzle flight velocity, a blunt forward drag face providing a high aerodynamic drag configuration for said bullet at subsonic flight velocities and rapid impact energy transfer, said drag face being substantially flat and extending over substantially the entire frontal area of said bullet, and a non-ablative, integral spike tip fixed forwardly of said drag face at a fixed distance in the flight of said bullet, said spike tip having a much smaller effective frontal area than said drag face, said spike tip being adapted to form a supersonic shock wave cone at the forward end of said bullet during the flight of said bullet, said spike tip and said drag face being positioned with respect to one another on said bullet so that for supersonic flight of said bullet said drag face is inside said shock wave cone formed by said spike tip, thereby providing a low aerodynamic drag configuration for said bullet at supersonic velocities, whereby said bullet maintains a high supersonic flight velocity for a preselected initial combat range after firing but then rapidly decelerates due to high aerodynamic drag after the bullet slows to a subsonic flight velocity, thereby reducing said bullet''s danger to objects and personnel outside of said combat range and reducing said bullet''s range.