Handgun Cartridge with Shear Groove Bullet

This application is a Continuation of U.S. patent application Ser. No. 17/686,549, filed Mar. 4, 2022, which is a Continuation of U.S. patent application Ser. No. 16/509,394, filed Jul. 11, 2019, which is a Continuation-In-Part application of U.S. patent application Ser. No. 14/722,076, filed May 26, 2015, which claims the benefit of U.S. Provisional Application No. 62/002,600, filed May 23, 2014, and claims the benefit of U.S. Provisional Application No. 62/696,804, dated Jul. 11, 2018.

The present invention generally relates to cartridges for use with handguns. More particularly, to a cartridge comprising a case with an inserted jacketed bullet having a shearing groove and a circumferential hinge imparted in the jacket of the bullet.

Contemporary cartridge and bullet design and construction have dramatically increased the terminal effectiveness of many premium line law enforcement handgun projectiles. Much of the improved effectiveness has been driven by FBI standardized terminal performance test protocols (FBI Penetration Test), which are a series of practically oriented tests to measure a bullet's ability to meet these performance standards. The tests measure expectable penetration in soft tissue after passing through particular barriers, including bare ballistics gel, heavy clothing, drywall, plywood, sheet metal and auto glass. The tests also measure uniform expansion and bullet retention weights after passing through such barriers and impacting soft tissue. An unresolved issue with the current technology of expanding bullets is that many have difficulty in maintaining integrity through such barriers. In particular, shifts in the FBI protocol scoring criteria have seen reduced performance against auto-glass.

One of the largest issues in bullet development is creating a design that performs well through all the FBI Protocol barrier tests. The most challenging is the Auto Glass test because it creates “wings” that protrude from the bullets that reduces penetration to unacceptable levels. The purpose of the FBI Penetration Test is to determine the following information regarding a particular cartridge: 1) the penetration performance of the cartridge's projectile, throughout the series of six tests (depth of penetration to nearest 0.25 inch, expansion of projectile, retained weight of the projectile); 2) the average velocity, both from a test barrel and a service weapon; and 3) the average accuracy, both from a test barrel and a service weapon. The test medium utilized is 10% ballistic gelatin (nominal), by weight.

Of the six tests, the Automobile Glass involves firing through one piece (15″×18″) of A.S.I. ¼ inch laminated automobile safety glass which is set at an angle of 45° to the horizontal and 15° to the side, resulting in a compound angle. The gelatin block is placed 18 inches behind the glass. This test event simulates a shot taken at the driver of a car from the left front quarter of the vehicle.

The Automobile Glass test has resulted in poor performances. In particular, jackets of hollow-point jacketed bullets, typically non-bonded, can be cut and torn by the hard and sharp edge of the fractured glass. This damage will then propagate sufficiently down and around the projectile form to mechanically separate the jacket from the lead core. The resulting terminal performance of the projectile has been substantially compromised due to the loss of mass and loss of expanded diameter. The loss of mass will typically reduce the residual momentum of the projectile sufficiently to prevent it from penetrating the prescribed minimum of 12 inches into ballistics gelatin. This insufficient penetration is viewed and scored as a major defect in performance by the FBI. Upon impact with the glass, the core of the projectile collapses and forward portions of the jacket peal back under the force of the impact and collapsing core. The impact forces contribute to a separation of the jacket, or jacket portions, from the core, which negatively impacts mass retention and performance. In contrast, a favorable result is one in which the jacketed bullet may expand in response to the pressure created by the impact, which is referred to as mushrooming or upset, but the bullet jacket remains connected to the core and the bullet maintains mass integrity to effectuate the required penetration.

The ballistics of cartridge bullets for handguns, including interior ballistics, which studies the projectiles movement inside the gun, exterior ballistics, which studies the projectiles movement between the muzzle and the target, and most notably terminal ballistics, which studies the projectiles movement in the target and is of high relevance in the FBI Standards Tests, is highly effected by cartridge and bullet design and construction. Design and construction of cartridges, including the cartridge case and the bullet inserted therein, effect issues dealing with performance, mass and jacket retention, and bullet expansion of a bullet fired through barriers prior to contacting a target. As such, specifics of the design and construction of handgun cartridges and cartridge elements, including cases, bullets and the insertion and engagement of the bullets in the cases, have direct effects on performance.

A cartridge for use handguns is a single unit of ammunition consisting of a case, primer, propellant and a projectile or bullet. The cartridge case is the main body of a single round and typically includes a body, which contains the propellant, and a case head or head, which is the rear end of the cartridge case, in which the primer or priming is inserted and the surface upon which the head stamp identification is imprinted.

Cartridges are typically either centerfire or rimfire. Centerfire cartridges are any cartridge intended for use in rifles, pistols and revolvers that has its primer central to the axis in the head of the case. Rimfire cartridges are flange-headed cartridges, wherein the priming mixture is inside the rim cavity.

Cartridges can further be categorized as rimless, rimmed or semi-rimmed. A rimless cartridge is a centerfire cartridge whose case head is of the same diameter as the body and has a groove turned forward of the head to provide the extraction surface. Rimmed cartridges have a rimmed or flanged head that is larger in diameter than the body of the case. Cartridges that are semi-rimmed include centerfire cartridges having a case head only slightly larger in diameter than the case body and an extractor groove just forward of the head. Some cartridges have a rim that is significantly smaller than case body diameter. These are known as rebated-rim designs, and almost always allow a handgun to fire multiple caliber cartridges with only a barrel and magazine change.

Revolver cartridges are considered rimmed cartridges, having a rim at the base of the case that is larger than the case body and which seats against or into the cylinder block to provide headspace control and to provide for easy extraction.

Pistol cartridges, such as semi-automatic pistol cartridges, are predominantly rimless. Such cartridges have a rim of the same diameter as the case body. An extractor engages this rim by entering a groove near the base of the case.

The projectile, or bullet, of conventional cartridges is typically a jacketed bullet. This is a bullet having an outer metallic cover over a core, which is commonly lead. Variations include full jacket, wherein the bullet jacket encloses most of the core with the possible exception of the base, and semi-jacketed, which is a bullet with a partial jacket exposing a lead nose. Jacketed bullets include bonded jackets, wherein the jacket is bonded to the inner core to create a surface to surface engagement between the jacket and the core, and non-bonded bullets, wherein the jacket is not bonded to the inner core material.

Further variations include hollow-point bullets, wherein the bullet includes a cavity in the nose to facilitate expansion upon impact. Such expansion is commonly referred to as bullet upset or mushrooming. Bullet upset in Exterior Ballistics is the expansion of a bullet upon impact with target. A mushroomed bullet is a bullet that has expanded upon impact into a mushroom-like shape. It is desirable to design and construct the cartridges and bullets so as to control such expansion to achieve desired results.

There have been numerous efforts to design standard caliber bullets for handguns to improve their performance. Such efforts have been directed to improving mass retention of the bullet after it strikes a barrier to maximize the impact penetration of the bullet on the target and to improving expansion of the bullet after it strikes its target to maximize damage to the target. Fragmentation or separation of the jacket causes a dramatic decrease in kinetic energy of individual components and thus the penetration and stopping power. In non-bonded jacketed bullets, such attempts in keeping the jacket and core coupled together on impact include creating a mechanical lock between the jacket and the core.

Issues also arise with bonded bullets. While bonded bullets have a reduced tendency to fail minimum penetration due to mass loss through these types of barriers, they are not widely accepted by the law enforcement market due to the increased expense of fabrication required to either electrolytically or chemically bond the jacket to the lead core.

It would be desirable to provide a design for such ammunition which improves jacket retention and controlled expansion resulting in terminal performance which meets current FBI standards, notably the Automobile Glass Test. It would be further desirable to provide such a design that is conducive to consistent performance and additionally requires minor modification to current toolsets allowing for minimal manufacturing cost increase.

The present invention relates to handgun cartridges, in particular rimless cartridges for pistols, with inserted bullets having a circumferential shear groove formed in the outer surface of the bullet jacket. The shear groove may act to release, separate or shear petals formed as a result of over-expansion after impact with the hard surfaces, allowing for better performance under current FBI standardized terminal performance test protocol conditions.

In embodiments, a rimless cartridge comprising a case and a bullet mounted therein. The bullet comprises a jacketed malleable core having a cylindrical body portion, an ogive or tapered portion, and a plurality of longitudinally extending paths of weakness, such as skives, formed in the ogive portion and defining petals there between and extending rearward from the mouth. The bullet comprises a circumferential shear groove positioned between a forward circumferential indentation imparted in the ogive portion and rearward circumferential indentation imparted in the body portion of the jacket. Upon firing and penetration of hard material, the forward circumferential indentation acts as a hinge folding normal expansion petals back and the shear groove acts to release, separate or shear the petals in the event of bullet impact with the hard surfaces results in over-expansion.

In embodiments, a rimless cartridge for firing in a handgun. The rimless cartridge comprises a case and a bullet inserted into a mouth of the case, wherein the bullet comprises a core and a jacket of metallic material at least partially enveloping the core. The bullet includes rearward cylindrical body portion and a forward ogive portion, wherein the forward ogive portion has a forward cavity and may include paths of weakening or skives formed in the jacket. In embodiments, the bullet may include a rearward circumferential indentation, a forward circumferential indentation and a circumferential shear groove positioned between the rearward circumferential indentation and the forward circumferential indentation, all formed or imparted in the jacket of the bullet. In embodiments, the shear groove extends into the jacket and may form an outwardly opening acute angle. In embodiments, after impact with a hard material, such as glass, the forward circumferential indentation acts as a hinge, folding normal expansion petals back. The shear groove acts to prevent over expansion or upset of the bullet by releasing, separating or shearing the expansion petals allowing securement of the core in the remaining jacket portion and the bullet to maintain mass for more effective penetration.

In an embodiment, a cartridge for firing in a handgun, wherein the rimless cartridge comprises a case and a bullet inserted into a mouth opening of the case. The bullet may comprise a core and a jacket of metallic material at least partially enveloping the core and include a rearward cylindrical body portion and a forward tapered portion. The bullet may further include a forward cavity and a plurality of skives defining a plurality of expansion petals in the jacket, each skive being axially oriented and having a forward end and a rearward end. In embodiments, the bullet may have a rearward circumferential indentation formed in the rearward cylindrical body portion, a forward circumferential indentation formed in the tapered portion and a circumferential groove positioned axially between the rearward circumferential indentation and the forward circumferential indentation.

In embodiments, the forward circumferential indentation may be axially positioned at or adjacent to the rearward end of at least one of the plurality of skives. In an embodiment, the circumferential groove is formed in the tapered portion of the bullet. The circumferential groove may extend into the jacket and form an outwardly opening acute angle. In an embodiment, the acute angle may be about 60 degrees. The circumferential groove may further have a bottom flat at an innermost portion of the circumferential groove.

In embodiments, a handgun cartridge comprising a case with a head and a case wall extend forwardly from the head defining an interior and a forward case mouth with propellant in the interior and a bullet in the case mouth, the bullet having a forward end, a rearward end, and an axis, the bullet comprising a core and a jacket at least partially enveloping the core, wherein the bullet has a cylindrical body portion and a tapered forward portion, the forward portion having a nose portion with an axially extending indentation therein, the jacket covering the body portion and at least partially covering the tapered forward portion, a plurality of skives defined in the jacket on the tapered portion and extending to the nose portion, a first groove extending circumferentially around the tapered forward portion in the jacket at rearward ends of the plurality of skives, the first groove extending a first groove depth into the jacket and having an first groove axial width, a second groove extending circumferentially around the tapered forward portion and positioned rearwardly of the first groove, the second groove extending a second groove depth into the jacket and having a second groove axial width, the second groove depth being greater than the first groove depth, a third groove extending circumferentially around jacket at the cylindrical body portion, the third groove having a third groove depth and a third groove axial width, the third axial width being greater than the first groove axial width and greater than the second groove axial width. In embodiments, the first groove provides a hinge for a plurality of pedals formed upon impact of the bullet with a target, the second groove forms a separation region for the plurality of pedals formed upon impact of the bullet with the target, and the third groove provides retention of the core in the cylindrical portion with the jacket at the cylindrical portion.

In embodiments, the forward circumferential indentation defines a first diameter of the bullet and the circumferential groove defines a second diameter. In an embodiments, the first and second diameters may be substantially equal.

In embodiments, the circumferential groove may be a cut-in cannelure, a formed groove, wherein material is removed in forming the groove, or a rolled-in groove, wherein the groove is formed without removing material. In an embodiments, the circumferential groove may be formed such that a cross section of the bullet at the forward circumferential indentation has a diameter of about 0.333 inches. In an embodiment, cross sections of the bullet at the forward circumferential indentation and at the shear groove each have a diameter of about 0.333 inches.

In embodiments, the bullet of the cartridge may a caliber chosen from the group consisting of 9 mm caliber, 10 mm caliber, 40 caliber and 45 caliber. In an embodiment, the bullet has a caliber and grain weight chosen from the group comprising 9 mm, 100-160 gr.; 40 s&w, 135-210 gr.; 45, 155-250 gr.; 357 sig, 100-160 gr.; 45 g.a.p., 155-250 gr.; and 10 mm auto, 135-210 gr. In an embodiments, the bullet is a 9 mm caliber bullet.

In an embodiment, a method of making a rimless cartridge sized and adapted to be used in a handgun comprising the steps of: a) drawing a sheet metal blank into a cup shaped jacket blank having a flat bottom and a generally uniform thickness wall; b) forming a malleable metal core in the cup shaped jacket blank against the bottom by swaging or molding the core directly into the blank; c) providing a plurality of axially oriented skives through the jacket wall; d) forming a cavity in the metal core at the open end of the cup shaped blank; e) deforming the end of the blank into an ogival or tapering front end portion of the bullet, wherein in the plurality of skives are formed in the tapering front end portion; f) imparting a rearward circumferential indentation into the body of the cup shaped jacket blank, such that jacket material is forced radially inward creating an internal circumferential indentation which extends into the bullet core; g) imparting a forward circumferential indentation into the body of the cup shaped jacket blank, wherein the forward circumferential indentation is formed in the tapering front end portion; and h) imparting a circumferential groove into the body of the cup shaped jacket blank forward of the rearward circumferential indentation and rearward of the forward circumferential indentation.

In an embodiments, the circumferential groove may formed in the tapering front end portion and the forward circumferential indentation may be axially positioned at or adjacent to a rearward end of at least one of the plurality of skives. In an embodiment, the circumferential groove extends into the jacket, forming an outwardly opening acute angle. The acute angle may be about 60 degrees.

In embodiments, diameters of the bullet at the circumferential groove and at the forward circumferential indentation may be equal. In an embodiment, the diameters may be about 0.333 inches. In an embodiment, the lengthof the bullet may be about 0.645 inches.

In embodiments, the shear groove circumferentially imparted in the jacket of the bullet approximately adjacent to the diameter transition portion of the bullet causes the jacket to shear or tear away when passing through auto glass, enabling deeper penetration in the FBI Auto Glass protocol test. The location and geometry of the feature is such that in all other FBI test barriers, this shear groove does not cause the jacket to shear away, only in the auto glass test. In embodiments, the shear groove may be either a cut in cannelure or groove where material is removed in the manufacturing process, or it can be rolled in without removing material.

In some application situations the bullet has to go through hard material, such as glass, before it penetrates the target soft material. In such situations, the hard material may cause the bullet to over expand, creating a larger front profile. This can slow the bullet down through target softer material, reducing the bullets penetration. In embodiments, the shear groove of the bullets herein counteracts the over expansion by allowing the expanding portion, which may include normal expansion petals and core segments, of the bullet to shear away, preventing over-expansion. If the bullet was deforming past a certain point, instead of it stopping the bullet short on penetration, the expanding forward portions of the bullet can break away to allow the core of the bullet to still reach target penetration. In the above discussed FBI testing protocol, this means 12 inches into a gelatin block.

During upset of the bullet, the shear groove may reduce forces that can cause separation of the jacket from the core initiated upon impact. In embodiments, the shear groove may be positioned and formed to act as a stress riser allowing tearing away of forward portions of the bullet while encountering hard barriers such as laminated auto-glass and the automobile glass in the Automobile Glass Test, allowing the remaining jacketed rear portion of the bullet to penetrate the soft target to an acceptable depth. The intentional mechanical separation of petal and segment material and the rearward jacketed core prevents the mechanical damage from propagating to the rear of the bullet allowing it to remain fully intact ensuring adequate mechanical retention of the jacket to the core through difficult barriers.

In an embodiment of the invention, there is disclosed a rimless cartridge for firing in a pistol. The rimless cartridge comprises a case comprising a forward cylindrical wall connecting to a rearward head having a neck and an annular flange. The forward cylindrical wall terminates at a leading edge and defines a bullet opening. The rearward head has an outermost diameter no greater than that of the forward cylindrical wall. The rimless cartridge further comprises a bullet inserted into the opening, the bullet comprising a core and a jacket of metallic material at least partially enveloping the core. The bullet has an aspect ratio of length to outermost diameter of about 1.05 to 2.00; and propellant in the case rearward of the bullet. The bullet has a rearward cylindrical body portion and a forward ogive portion, the forward ogive portion having a forward cavity and radial segments formed in the core and corresponding paths of weakening formed in the jacket. The rearward cylindrical body portion has a rearward circumferential indentation and a forward circumferential indentation position in the ogive portion of the bullet. A shear groove is position between the indentations and extends into the jacket. In embodiments, the shear groove forms an outwardly opening acute angle with a flat portion at the apex.

Various embodiments can include non-bonded expanding bullets. Embodiments include cartridges having various calibers including: 9 mm caliber, 10 mm caliber, 40 caliber and 45 caliber. The bullet can have an aspect ratio of length to outermost diameter of about 1.05 to about 2.00. The aspect ratio of the rimless cartridge length to the bullet diameter can be about 2.30 to about 4.45. In some embodiments, the bullet of the cartridge can have a ratio of the bullet length to the bullet diameter is from about 1.35 to about 1.95. In some embodiments, the bullet is a caliber chosen from the group comprising: 9 mm caliber, 10 mm caliber, 40 caliber and 45 caliber.

In some embodiments, the rimless cartridge of the present invention includes a case having a leading edge defining an opening and a bullet inserted into the opening of the case. The bullet comprises a jacketed core having a rear end and a forward end having an opening, a body portion, an ogive portion, and a transition portion. The transition portion is positioned between the body portion and the ogive portion. The bullet further includes a shear groove position adjacent the transition portion. In embodiment, the shear groove is positioned forward of the transition portion.

Aspects and embodiments of the present invention are advantageous at least in that the cartridges of the present invention requires only minor modification to current toolsets allowing for minimal cost increase, if any, while markedly improving the terminal performance of the resulting cartridge. The design further does not require substantive development of new and complex components or processes to allow fabrication of production volumes and can be implemented on conventional, in place equipment.

The above summary of the various representative aspects of the invention is not intended to describe each illustrated aspect or every implementation of the invention. Rather, the aspects are chosen and described so that others skilled in the art can appreciate and understand the principles and practices of the invention. The figures in the detailed description that follow more particularly exemplify these aspects.

Still other objects and advantages of the present invention and methods of construction of the same will become readily apparent to those skilled in the art from the following detailed description, wherein only the preferred embodiments are shown and described, simply by way of illustration of the best mode contemplated of carrying out the invention. As will be realized, the invention is capable of other and different embodiments and methods of construction, and its several details are capable of modification in various obvious respects, all without departing from the invention. Accordingly, the drawing and description are to be regarded as illustrative in nature, and not as restrictive.

While the present invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the present invention to the particular aspects described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

While this invention may be embodied in many different forms, there are described in detail herein specific embodiments of the invention. This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated.

For the purposes of this disclosure, like reference numerals in the figures shall refer to like features unless otherwise indicated.

shows a cartridgeandshows a bulletconstructed in accordance with an embodiment of the invention. The cartridgeshown is a rimless cartridge, which is a centerfire cartridge whose case head is of the same diameter as the main body of the case. In embodiments, the cartridgemay include a rear end, a forward endand a longitudinal axis. The cartridgemay further include a casehaving an interior cavity, which may contain propellant, and a bullet, the bullet being received and held partially within the interior cavity.

In embodiments, the casemay include a body, a case mouthat a forward endand a case headat the rearward end. The bodymay include a wall, which may be cylindrically shaped around the axisof the cartridgeand define the interior cavity. The wallmay have a cross-sectional symmetry and an outer diameter that may be substantially constant along its length. At least a portion of the body wallmay define an outer most diameter of the cartridge. The forward endof the casemay include a forward periphery or leading edgewhich defines the case mouth. The case mouthmay be shaped to receive and hold the bulletvia a friction fit engagement. In an embodiment, the bulletmay be held in the mouthof the casevia an outer crimp in the forward endof the case.

In embodiments, the case headmay include a groovethat may provide an extraction surface and a flange or rimhaving an outer diameter. The case headfurther may define a bottomof the caseand may further house a primer(shown in phantom lines). As mention above, the case head, including the rim, may be the same diameter as the case wall. In an embodiment, the rimmay be of lesser diameter.

In an embodiment, the case may be a bottleneck case, as shown in. The bottleneck casemay include a bodyhaving a case wallwith an outer diameter and a distinct angular transition portionnecking down to a smaller diameter at a neck portionof the case. The neck portionmay include a forward edge, which defines the case mouth.

illustrates a bulletin accordance with an embodiment of the invention.shows a cross-section view of the bullet, revealing a core. In embodiments, the bulletmay include a forward end, a rearward end, a cylindrical body portionhaving a width, a forward tapered portion configured as an ogive portion, a length, a jacketand the core. The jacket, which may form the outermost surface of the bullet, may house and confine the core. The bulletmay further include a base, which may comprise a heal portionand a bottom. In embodiments, the heal portionmay be angled radially inward toward the bottom, forming a boat tail shape. In embodiments, the diameter of the basemay be in line with that of the body portionof the bullet.

In embodiments, the body portionmay have a lengthforward from the heal portion. In some embodiments, wherein the heal portionis not boat tail shaped, the length may be forward from the bottom. In an embodiment, the heal portionmay be angled and have a radius of about 0.020 inches.

In embodiments, the outermost surface of the body portionmay comprise one or more annular outer surfaces or bearing surfaces. At least in the present application, “bearing surface” is the radial outermost surface portions of the bulletthat come into direct contact with the interior surface of a barrel bore of a firearm when moving through the barrel. In embodiments, bearing surfaces may also be considered annular outer surfaces of the bodyof the bulletwith the largest diameters.

In at least some embodiments, the bearing surfacecomprises a forward bearing surfacehaving a lengthand a rearward bearing surfacehaving a length. The body portionmay be substantially cylindrically shaped with cross-sectional symmetry in the lengths of the bearing surfaces,. In embodiments, the cross-sectional diameter of the bodymay be substantially constant in diameter along the bearing surfaces,. In some embodiments, the rearward bearing surfacemay be axially longer than the forward bearing surface, as shown in. In some embodiments, the forward bearing surfacemay be axially the same or longer than the rearward bearing surface. In an embodiment, the body portionmay have a cylindricityof about 0.0005, excluding the rearward circumferential indentationand the heal portion.

In embodiments, the ogive portion or ogive, may be a portion of the bulletthat is forward of bearing surface. The ogive portionmay have circumferential symmetry around an axisof the bulletand may vary in rate of change of diameter or in curvature of its outer side profile arc from the forward endrearward to the forward end of the body. In embodiments, the ogive portionmay have a substantially decreasing diameter or a positive or inward curvature substantially from bearing surfaceto the forward endof the bullet. The ogivecan be generally conical or frustoconical in shape. In various embodiments of the invention, ogiveconfigurations include a tangential ogive, a secant ogive and a truncated cone.