Patent Grant
8640623
When WWII started, the standard U.S. Army infantry rifle was the M1 Garrand, which used the 30-06 cartridge. (The 30-06 cartridge notation breaks into the 30 being the caliber and 1906 the year it was adopted; using the modern ammunition notation system the projectile diameter is 7.62 mm and the cartridge length is 63 mm, or 7.62 mm×63 mm). This was the world's first semi-automatic infantry weapon to enter mass production and be issued to front line troops. While this is a very powerful cartridge effective at ranges of up to 1,000 meters, the size of this cartridge restricted the number of rounds loaded to only eight in the M1's en bloc ammunition clip system. (The en bloc clip was state of the art in the 1930s and was used to load the M1's internal magazine, but became obsolete with the modern external magazine system adopted by later assault rifles, which allow the storage of 20-30 rounds in magazines that could be easily topped off and replaced).
During WWII, the standard German Army bolt action Mouser 98 infantry rifle used a 7.92 mm×57 mm round (also known as the 8 mm×57 mm in Europe or 8 mm Mauser) with qualities and performance similar to that of the U.S. 30-06 cartridge. However, German analysis of how their infantry weapons were actually used in combat indicated that most engagements were at ranges of less than 400 meters and often required high rates of fire, so having a large, powerful cartridge that was effective to 800-1,000 meters was a waste of scarce materials (cartridge brass and gunpowder) and logistic resources. They designed a smaller, lighter, semi and automatic assault weapon designated StG-44 (Sturmgewehror or storm rifle 44) which used a shortened version of the 7.92 mm round already in production, designated 7.92 mm×33 mm Kurtz (German for short), stored in a detachable 30 round magazine.
After WWII, Russian designer Mikhail Kalashnikov continued to build on the StG-44 concept when he designed the AK-47 (automatic Kalashnikov 1947). Russia used (and continues to use today) a 7.62 mm×54 mm round for their machine guns and sniper rifles. The AK-47 uses a shortened version of the 7.62 mm×54 mm round designated 7.62 mm×39 mm, which allows 30 rounds to be carried in the standard, curved AK-47 magazine. Like the German StG-44 design, the 7.62 mm×39 mm round is designed to be effective at shorter ranges, with the reduced size and weight facilitating the supply of the large number of cartridges needed for high volume fire.
In contrast, after WWII the U.S. Army adopted the more traditional M-14, which used a modern 20 round external magazine to facilitate rapid reloading, and the shorter 7.62 mm×51 mm round, which became the standard NATO assault rifle, sniper rifle, and machine gun round. This weapon was employed in the Korean conflict, and the early years of Vietnam. But the M-14 was a larger, heavy weapon with only 20 rounds available in the standard external magazine, so the U.S. Army started to consider other assault weapon designs that were smaller, lighter, had less recoil, and carried more rounds of ammunition.
One weapon that stood out in the early 1960's was Eugene Stoner's AR-15, which was originally designed for the U.S. Air Force. It employed a 5.56 mm×45 mm cartridge, which allowed 30 rounds to be carried in the standard external magazine. This weapon was much lighter than the M-14 with reduced recoil, and the high velocity 5.56 mm round had similar effectiveness at shorter ranges (less than 400 m). Another design, the M-16, developed a bad reputation in the 1960s when the Army decided to substitute one type of gunpowder for another, which caused excessive fouling and residue in the weapon and resultant malfunctions. Another Army management and training miscue was promotion of the belief that M-16s did not require regular cleaning, so cleaning kits and instruction were not supplied to front line troops. Once these management and training deficiencies were rectified, the M-16 performed as designed, and regained its reputation as an accurate, easy to use, and effective assault rifle at less than 400 meters.
The newest version of the M-16 is the M-4. It is a carbine with a shorter barrel and collapsible stock, allowing easier handling in urban situations. The original triangular barrel heat shield has been replaced with either a round cover, or more commonly, metal rails that allow the easy installation of accessories like bipods, grenade launchers, etc. New sights, like the Trijicon Advanced Combat Optical Group (ACOG) allow fast, precise aiming even in low light conditions. However, the shorter 14.5 in barrel also reduced muzzle velocities and potential ammunition effectiveness.
Current Assault Rifle Ammunition Caliber, a Compromise:
The U.S. Army, and then NATO, converted their assault rifles from 7.62 mm×51 mm to 5.56 mm×45 mm ammunition because they could double the number of rounds sent downrange for roughly the same given volume, weight, and cost. The smaller size and mass of the 5.56 mm projectile (62 grains for the NATO standard M855/SS109 round) is less than half that of the standard 7.62 mm NATO round (147 grains for the M80 ball, 151 grains for the M61 armor piercing), but in theory the higher velocity maintains the desired energy level at combat ranges of less than 400 m. However, the shorter barrel of the M4 lowers the bullet velocity and potential yawing, which is a major factor in this rounds potential effectiveness. There have also been reports that M855 effectiveness is reduced when impacting the thin, low body mass combatants found in Africa and Afghanistan.
However, the future development potential of 5.56 mm×45 ammunition is limited because materials science and design cannot overcome simple physics, as the following Wikipedia chart illustrates:
Comparison of 5.56 Mm Versus 7.62 Mm NATO:
Proposed 6.8 mm Remington Special Purpose Cartridge (SPC) Round:
The advantages of the M855/SS109 5.56 mm×45 mm round over the M80 7.62 mm×51 mm round (twice as many rounds per a given volume and weight, similar effectiveness in ranges less than 400 m when fired from long barreled weapons) are well known, as are the potential 5.56 mm development limitations (trend toward short barreled carbines which lowers muzzle velocities, lower body mass combatants in Africa and Afghanistan decreases wounding effectiveness, and longer engagement ranges).
One effectiveness solution gaining in popularity is a new cartridge, the 6.8 mm×43 mm Remington SPC. The 6.8 mm×43 mm round can fit in standard magazine wells of M-16 type weapons in widespread service. Converting existing 5.56 mm weapons to the 6.8 mm SPC only requires the replacement of the barrel, bolt, and magazines of 5.56 mm chambered weapons. According to Wikipedia, this round delivers 44 percent more energy than the 5.56 mm round in the key 100-300 m range. It also maintains a ballistic performance similar to the NATO 7.62 mm round and superior to the 5.56 mm and Russian 7.62 mm×39 mm rounds out to 400 m:
Modern Assault Rifle Design Examples:
Due to the continuing discussions of assault rifle cartridge tradeoffs, several manufactures have started manufacturing their latest designs in both 5.56 mm and 7.62 mm, with trials of 6.8 mm SPC weapons continuing. Hecker & Koch are offering two production versions of their latest design, the HK 416 (5.56 mm), the developmental HK 416 6.8 mm SPC (6.8 mm), and HK 417. The 5.56 mm and 6.8 mm SPC models can use the same receiver and magazine, while the HK417 must use a different receiver and magazine.
Assault Rifle Ammunition Velocity and Energy Tradeoffs:
In addition to the volume, weight, and number of available round tradeoffs mentioned earlier in the 5.56 mm and NATO 7.62 mm comparisons, there are also velocity, energy, and ballistic trajectory implications to choosing one round vice another. As shown in the below chart, probably the biggest disadvantage to the AK-47 7.62 mm×39 mm cartridge is the velocity and bullet drop at the 400 yard/meter distance as compared to the Western 5.56 mm, 6.8 mmSPC, and 7.62 mm NATO rounds. This is the major reason the Russian 7.62 mm×39 mm round was never adopted by Western militaries.
While the 6.8 mm SPC has many advantages over the current 5.56 mm/M855 cartridge, it is currently a non-standard developmental round which has not been approved for NATO service, which has standardized on the 5.56 mm×45 mm and 7.62 mm×51 mm rounds for logistic support reasons. Replacing the existing barrels, bolts, and magazines of existing 5.56 mm weapons is also not a trivial expense, nor is buying new weapons to replace millions of existing assault rifles. While discussions on how to improve modern assault rifle design has been focused on cartridge types, there are other potential approaches that can leverage existing investments by improving 7.62 mm×51 mm ammunition design.
The Duplex Load:
Another approach to maximizing the assault rifle ammunition effectiveness is to have two projectiles fired from the same cartridge, which has been termed a duplex load or cartridge. According to the Gun Zone (http://www.thegunzone.com/salvo.html), research on duplex or salvo loads go back a couple of decades:
5.56×45 mm/5.56 NATO:
According to the Gun Zone, similar initiatives have also been taken for 7.62 mm×51 mm cartridges:
7.62 mm NATO:
The NATO 7.62 mm M198 Duplex Ball round with two similar 84 grain bullets failed to gain acceptance, evidently due to poor accuracy. The two bullets/projectiles had similar weights and shapes, but evidently the dispersion as the range increased was deemed unsatisfactory. At short range, dispersion increases hit probability, but at long range excessive dispersion lowers it. Ideally, if dispersion could be controlled so that both projectiles dispersed only 10-20 mm per hundred meters of flight, then a 7.62 mm duplex cartridge with projectiles equal to or greater than the 62 grain M855 could offer the best of both calibers—greater penetration, effectiveness, and range than 5.56 mm rounds like the M855, but with same volumetric efficiency (e.g., number of projectiles downrange per a given weight and volume).
Bullet Design Compromise: Soft vs. Hard Target Penetration
One of the major challenges of modern assault rifle and machine gun bullet design is the need to be effective against both soft and hard targets—simultaneously. Traditional soft target bullet design emphasizes expansion after target impact. For example, most modern rifle rounds for shooting animals typically have a soft lead core with a copper jacket. (Lead is a soft metal that will foul or leave deposits in gun barrel rifling groves used to impart spin to a projectile for increased accuracy—the copper jacket minimizes these deposits). Upon impacting animal tissue, the soft lead core expands, so that the size of the projectile typically increases in diameter to twice that (or more) of the original caliber. This design gives the expanded bullet a mushroom appearance, and increases the wound channel size and energy transfer to the target. Some modern bullet designs (like the M855) increase the size of the wound channel by yawing after impact. However, in the case of the M855, this characteristic is highly dependent upon velocity. Once velocity falls below a certain level, due to using a short-barreled carbine, or velocity bleed (due to air resistance) at extended ranges (as noted in previous citations). Some modern bullet designs (like the M855) are also deliberately designed so that cannelure (a groove around the cylinder of a bullet) will increase the tendency of the projectile to fragment as it yaws, which is another way of increasing the wound channel, and energy transfer. However, if the lower velocity (M855) projectile does not yaw, then cannelure design and placement will not increase fragmentation.
Penetrating and defeating hard targets requires a diametrically opposite projectile design philosophy. Projectile expansion is to be avoided at all costs, because it will limit penetration. This is done by using hard metals (steel, tungsten, depleted uranium, etc.) for the penetrator. Small projectile diameters are better than larger ones because the reduced frontal area will concentrate all of the projectile energy (projectile mass times velocity) on a smaller area, increasing penetration. This design approach is taken to the logical extreme for Hyper Velocity Armor Piercing Fin Stabilized Discarding Sabot (HVAPFSDS) tank rounds. These projectiles look like darts, with very high length to diameter ratios.
The normal or preferred way to address both of these requirements is to develop a separate projectile or cartridge for each requirement. Unfortunately, this means carrying two different type rounds in the field, and changing magazines prior to engaging the different targets. And due to modern body armor (Kevlar vests fitted with ceramic plate like the Small Arms Protective Inserts), which can stop some types of 5.56 mm and 7.62 mm ammunition, you might actually need to use both of the soft and hard target defeat options at the same time to defeat the enemy combatant.
In light of the shortcomings and limitations of the current 5.56 mm, 6.8 mm, and 7.62 mm cartridges, there is a desperate need for a more effective form of ammunition that can combine anti-personnel and anti-armor effects into a single round without the need to switch between two types of ammunition or to slow down the rate of firing.
The terms “MPTNP” and “DPTNP” as used herein refer to some embodiments of the claims. “MPTNP” stands for “Multiple-Purpose Tandem Nested Projectile” and “DPTNP” stands for “Dual-Purpose Tandem Nested Projectile.” Both of these terms are interchangeable with one another and no limitations should be construed when either of the terms is used instead of the other. Particularly, the use of the terms “DPTNP” or “Dual-Purpose Tandem Nested Projectile” may be used to describe a “MPTNP” or “Multiple-Purpose Tandem Nested Projectile” and therefore the use of the terms “DPTNP” or “Dual-Purpose Tandem Nested Projectile” should not be taken to mean that only two purposes may be fulfilled by the projectile, instead that multiple and many purposes may be fulfilled by the projectile.
Some embodiments of the claims will meet the needs described at the end of the background section and may include a multiple-purpose projectile assembly capable of being projected comprising an outer member and an inner member. The outer member defines a first projectile and has at least one communicating portion, and the inner member defines a second projectile. The inner member is located adjacent to the communicating portion of the outer member prior to the projection of either projectile. The projecting of either of the outer member or the inner member causes the projecting of the other of the outer member or the inner member.
Some of the advantages that may be provided by some embodiments are detailed below. Other advantages may additionally be provided by some embodiments and are envisioned to be provided under the scope of the attached claims.
Current 7.62 mm rounds have a weight and volume approximately twice that of current 5.56 mm rounds; doubling the number of 7.62 mm projectiles per cartridge negates one of the primary reasons 5.56 mm rounds were adopted. However, the 7.62 mm DPTNP design of some embodiments does not just double the number of projectiles—it allows each of the two projectiles to be optimized for their specific soft and hard target defeat functions. This means that one 7.62 mm DPTNP round is not just equivalent to two 5.56 mm rounds; it means that each of the 7.62 mm projectiles could be significantly more effective than two standard 5.56 mm projectiles. While 7.62 mm cartridges are roughly twice as expensive as 5.56 mm cartridges, a 7.62 mm DPTNP round may only be about 10 percent (cost of the extra internal primer and base bleed propellant) more expensive to manufacture, and may not require any special handing, or modifications to 7.62 mm weapons.
All assault rifles and machine guns have a cyclic rate of fire—so many rounds per minute, usually 500-600. Rifles and machine guns armed with DPTNP rounds may have approximately twice the effective rate of fire, without any weapons modifications, since each round fired is actually launching multiple projectiles instead of only one. Since continuous firing generates a lot of heat, most training programs stress the need to fire in bursts of several rounds at a time. Some assault rifles have a burst fire position on the safety switch, with three rounds being typical. When loaded with the DPTNP round, a single shot sends at least two projectiles downrange, at least doubling the rate of fire; a “double tap” would therefore send at least four projectiles downrange, at least two designed for soft targets, and at least two for hard targets. Another way to look at the DPTNP advantage is that an M-4 normally has a 30 round magazine, while an equivalent 7.62 mm assault rifle has a 20 round magazine. However, the 20 round 7.62 mm equipped with DPTNPs of some embodiments will send at least 40 projectiles downrange—at least a thirty-three percent increase over the M-4 using standard projectiles. In addition, assault rifle and machine guns are generally rated to fire a specific number of rounds before their barrels are replaced; this same observation applies to the entire weapon. With a DPTNP round, the weapon is subjected to the normal wear and tear of single round ammunition but at least twice as many rounds go downrange, significantly reducing long term logistic costs.
These and other features, aspects and advantages of some embodiments are more readily apparent with reference to the detailed description and accompanying drawings.
For a fuller understanding of the nature of some embodiments, reference should be made to the following detailed description taken in conjunction with the accompanying drawings in which:
Like reference numerals refer to like parts throughout the several views of the drawings.
Unless otherwise defined, all terms, and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by one having an ordinary skill in the art.
Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements presented in the attached claims. Some embodiments have been described for the purpose of illuminating one or more of the potential ways in which the specific features and/or elements of the attached claims fulfill the requirements of uniqueness, utility and non-obviousness.
Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments.
Any and all details set forth herein are used in the context of some embodiments and therefore should NOT be necessarily taken as limiting factors to the attached claims. Any descriptions of elements and/or features and/or the materials used to create those elements or features, or examples or methods included in the descriptions of the various embodiments are nonlimiting and are given as an illustration only. Accordingly, the embodiments can be manufactured, distributed, used, practiced, and carried out in numerous ways.
The attached claims and their legal equivalents can be realized in the context of embodiments other than the ones used as illustrative examples in the description herein.
Referring to the several views of the drawings, the multiple-purpose projectile assembly is shown in accordance with at least one embodiment of the invention. In each of the several views, the projectile assembly is generally indicated as 10.
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The first projectile 20 and the second projectile 30 travel along ballistic trajectories once fired. A ballistic trajectory is the path that a projectile takes after a propulsive force is terminated and the projectile is acted on by gravity and aerodynamic drag. In some embodiments, the ballistic trajectory of the second projectile 30 may be made similar or identical to the ballistic trajectory of the first projectile 20. In some embodiments, ballistic properties (properties having to do with the velocity or the ballistic trajectory of the projectile) of one or both projectile may be changed by changing one or more physical properties of one or more components of the multiple-purpose projectile assembly 10. More specifically, in some embodiments, ballistic properties of one or both projectiles may be changed by changing the diameter and/or the length and/or the weight of those projectiles. Additionally, in some embodiments, ballistic properties of one or both projectiles may be changed by changing the amount of the propellant 40 used and/or by changing the burn rate of the propellant 40.
An example of one embodiment will now be described. The scope of the attached claims is not limited to the example below.
A dual-purpose projectile assembly capable of penetrating both hard and soft targets and that is capable of being fired from a 7.62 mm weapon having a barrel, a bore, a chamber, and a muzzle. The dual purpose projectile assembly includes an outer member, an inner member, a propellant, a base bleed gas, and a primer.
The outer member defines an anti-personnel projectile made from a soft metal such as lead and/or copper etc. The anti-personnel projectile has a wide diameter that contributes to expanding the projectile upon impact with a target. The anti-personnel projectile includes a cavity therein, the cavity having a scored surface having multiple scores. The scores increase the likelihood that the outer member will separate into multiple fragments upon impact with a target. Both the expansion of the outer member upon impact and the separation of the outer member into fragments upon impact specifically increase the capability of the projectile to cause damage to soft targets such as humans or animals, because expansion increases the area of the wound caused and increases the energy transfer to the target, while fragmentation splits the projectile into smaller, dispersing projectiles that may spread through a soft target and damage multiple portions of the target (e.g. damage multiple organs in a person). The anti-personnel projectile travels along a ballistic trajectory after being fired from a weapon that terminates at the point of impact with a target. This trajectory, and the speed at which the projectile travels along the trajectory, are both changeable in response to changes in the diameter and/or the length and/or the weight and/or the shape of the anti-personnel projectile.
The inner member defines an armor-penetrating projectile made from a hard metal such as steel, tungsten, depleted uranium, etc. The armor-penetrating projectile has a narrow diameter that contributes to preventing any deformation or expansion of the projectile upon impact with a target. Both the narrow shape and the hard metal material specifically increase the capability of the armor-penetrating projectile to penetrate hard targets such as tank armor or body armor. The anti-personnel projectile partially fills the cavity of the anti-personnel projectile prior to firing. The firing of the projectile assembly causes the simultaneous firing of the anti-personnel projectile and the armor-penetrating projectile, wherein the armor-penetrating projectile is fired along the same ballistic trajectory of the anti-personnel projectile (i.e. the armor-penetrating projectile will hit the exact same spot of the exact same target that the anti-personnel projectile hits). This trajectory, and the speed at which the armor-penetrating projectile travels along the trajectory, are both changeable in response to changes in the diameter and/or the length and/or the weight and/or the shape of the armor-penetrating projectile.
The propellant defines a base bleed gas generator and is capable of being detonated and is housed within the cavity of the outer member. The propellant is located between the outer member and the inner member. When the propellant is detonated, it increases the pressure of the cavity of the outer member. This increased pressure applies a force to the outer member (in the forward direction of the projectile assembly's trajectory) and a force to the inner member (in the opposite direction of the projectile assembly's trajectory). This causes the inner member to withdraw from the cavity of the outer member. This withdrawal can only occur after the projectile assembly has left the bore of the weapon, for when the projectile assembly is still within the bore, the pressure in the bore is so strong that it prevents the projectile assembly from separating into the two projectiles. The withdrawal defines an increased separation between the anti-personnel and the armor-penetrating projectiles. The detonation of the propellant causes the propellant to burn at a predetermined burn rate, wherein changing the amount of the propellant and/or the burn rate of the propellant may change the ballistic trajectories of one or both projectiles and/or the speed of one or both projectiles.
The base bleed gas is generated by the burning of the propellant. It is released into the cavity of the outer member after the propellant begins to burn, subsequently filling the cavity and expanding outwards from the cavity. The base bleed gas increases the pressure of any space that it fills. By increasing the pressure of the cavity and the space behind the anti-personnel projectile, it reduces the drag experienced by the anti-personnel projectile, offsetting the difference in drag experienced between both projectiles due to the armor-penetrating projectile being narrower (thus experiencing less drag). Thus, the base bleed gas may allow the anti-personnel projectile to be able to travel as far and as fast as the following armor-penetrating projectile.
The primer is capable of being detonated and is housed within the cavity of the outer member, adjacent to the propellant. The detonation of the primer is caused by the driving of the armor-penetrating projectile into the primer, because the primer is an extremely sensitive explosive that detonates on contact. The driving of the armor-penetrating projectile into the primer is caused by the firing of the projectile assembly. The detonation of the primer provides the necessary activation energy required by the propellant to detonate, therefore it detonates the propellant.
Throughout the detailed description and the accompanying drawings enclosed herein, some embodiments have been shown, described and detailed, wherein a variety of possible elements and/or features may be formed and configured in different ways. Accordingly, any and all possible combinations of the elements and/or features described in accordance with these various embodiments may be desirable to manufacturers and/or may help to more successfully meet customers' specific needs and/or preferences. Consequently, any and all possible combinations of the features or elements of one embodiment or more than one embodiment or all embodiments mentioned herein are fully considered within the spirit and scope of the attached claims and their legal equivalents.
Thus, some embodiments of a multiple-purpose projectile assembly for being projected have been disclosed. Other embodiments are contemplated and envisioned as well, and therefore it is recognized that departures from the embodiments described in this disclosure may certainly exist within the spirit and scope of the attached claims. Those having an ordinary skill in the art will envision other possible variations and modifications to features and/or elements of the embodiments, and they will envision other possible embodiments, all of which may fall within the spirit and scope of the attached claims. The spirit and scope of the attached claims is therefore not limited by the descriptions and illuminations of the embodiments that have already been presented, but rather the spirit and scope can only be defined by the attached claims and their legal equivalents as interpreted under the doctrine of equivalents. Variations, alternatives, adjustments, modifications, tunings, and deviations from the embodiments of the instant disclosure are fully contemplated and envisioned within the spirit and scope of the attached claims.
This non-provisional patent application is based on provisional patent application Ser. No. 61/478,118 filed on Apr. 22, 2011.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3450050 | Robinson | Jun 1969 | A |
| 3680485 | Zaid et al. | Aug 1972 | A |
| 3802345 | La Costa | Apr 1974 | A |
| 3862600 | Tocco | Jan 1975 | A |
| 4777882 | Dieval | Oct 1988 | A |
| 4922826 | Busch et al. | May 1990 | A |
| 5796031 | Sigler | Aug 1998 | A |
| 7806053 | King et al. | Oct 2010 | B1 |
| 8191478 | Herbage et al. | Jun 2012 | B2 |
| 8250987 | Morley et al. | Aug 2012 | B1 |
| 20120234198 | Carmel | Sep 2012 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20120266773 A1 | Oct 2012 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61478118 | Apr 2011 | US |
