Patent Grant
10508891
The present invention relates to firearms and more particularly to a stoppage-inducing ammunition cartridge.
Most semi-automatic pistols' cycle of operation consists of feeding, chambering, locking, firing, unlocking, extracting, and ejecting a prior art cartridge 10 (shown in
A semi-automatic firearm's cycle of operation can be interrupted by numerous failures, which are generally cleared by one of two techniques. Expertise in these clearing techniques is essential to anyone relying on a semi-automatic firearm for protection. Law enforcement officers and other trained professionals practice these clearing techniques on a regular basis to ensure their proficiency. Various products have been developed to facilitate training in these clearing techniques.
The Action Trainer Dummy Round manufactured by S.T. Action Pro, Inc. of Coca, Fla. simulates a failure to fire malfunction. The failure to fire malfunction is easily created by inserting the Action Trainer Dummy Round into a magazine. When the Action Trainer Dummy Round is chambered, it will not discharge because it is an inert round. The shooter uses the tap/rack clearing technique by tapping the magazine's baseplate to ensure the magazine is properly positioned and then racking the slide to clear the chamber and cycle a new round. However, when the Action Trainer Dummy Round is used to simulate a failure to extract malfunction, shooters must hand place the dummy round in the chamber, then let the slide go forward on a magazine containing additional cartridges, live or dummy. This forces the next round from the magazine into the back of the dummy round in the chamber. Then, the shooter must place the gun in a shooting position and pretend they were in the middle of a course of fire when the malfunction occurred. Then the shooter practices clearing the malfunction. This leads to unrealistic training that becomes cumbersome and ineffective.
The Hard Malfunction Device manufactured by Range Systems, Inc. of New Hope, Minn. is placed in the bottom of a magazine to cause a full stoppage of a firearm occur during a course of fire to simulate a double feed or failure to extract malfunction. The Hard Malfunction Device is not a cartridge and cannot be cleared with the tap/rack technique. Instead, the device forces the shooter to remove and discard the magazine it is in. This is again an unrealistic training method, as this type of stoppage may occur with a loaded magazine that is of value to the shooter.
Another way of producing a failure to extract malfunction is to file down the hook 26 on the pistol's extractor so the hook cannot grab onto the cartridge case head correctly. This approach has the disadvantage of requiring an armorer to swap the pistol's extractor or for a trainee to use a designated pistol with a malfunctioning extractor to run this drill. It also limits what else can be accomplished at the same time since the stoppage cannot be limited to just one round (all rounds are affected).
Therefore, a need exists for a new and improved stoppage-inducing ammunition cartridge that discharges the same as a conventional live cartridge, but subsequently creates a failure to extract malfunction that enables realistic training of the clearing technique. In this regard, the various embodiments of the present invention substantially fulfill at least some of these needs. In this respect, the stoppage-inducing ammunition cartridge according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in doing so provides an apparatus primarily developed for the purpose of providing a training ammunition cartridge that discharges the same as a conventional live cartridge, but subsequently creates a failure to extract malfunction that enables realistic training of the clearing technique.
The present invention provides an improved stoppage-inducing ammunition cartridge, and overcomes the above-mentioned disadvantages and drawbacks of the prior art. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide an improved stoppage-inducing ammunition cartridge that has all the advantages of the prior art mentioned above.
To attain this, the preferred embodiment of the present invention essentially comprises a case having a rear head surface, a circumferential extractor groove forward of the rear head surface, a body portion forward of the circumferential extractor groove defining a case axis perpendicular to the rear head surface, and a forward mouth, a primer received in the case, a propellent within the case, a bullet received in the forward mouth, and the circumferential extractor groove being defined in part by a rear extractor surface angularly disposed with respect to a plane perpendicular to the case axis, such that an extractor adapted to engage a groove surface perpendicular to the case axis will have limited effect at extracting the cartridge from a firearm chamber after discharge. The rear extractor surface may be a frustoconical surface. The rear extractor surface may be a tapered surface. The tapered surface may be acutely angled with respect to the case axis. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims attached.
There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated.
The same reference numerals refer to the same parts throughout the various figures.
An embodiment of the stoppage-inducing ammunition cartridge of the present invention is shown and generally designated by the reference numeral 100.
It should be appreciated that the primer 112, propellant 114, and bullet 116 enable the stoppage-inducing ammunition cartridge 100 to fire exactly like prior art ammunition cartridge 10 with the shooter experiencing a normal sense of recoil. Thus, the shooter has no warning that the stoppage-inducing ammunition cartridge has been chambered until a failure to extract malfunction is experienced when the firearm attempts to chamber another round as the firearm cycles after discharge. The rear extractor surface 118 and groove surface 120 are changed relative to the extractor groove 14 of prior art ammunition cartridge 10 to remove the lip 22, which is a flat surface the hook 26 of the extractor 24 pulls against. However, the rear extractor surface and groove surface of the stoppage-inducing ammunition cartridge 100 still permit the hook to get some purchase on the groove surface so the case 122 can be removed during the clearing process. However, the limited purchase of the hook on the grooves surface prevents the extractor from properly and completely removing the case during the violent cycling process following discharge of the stoppage-inducing ammunition cartridge 100. This limited effect of the extractor at extracting the case from a firearm chamber after discharge creates a realistic failure to extract malfunction for training purposes.
For a 9 mm Luger cartridge when cutting the dimensions of the circumferential extractor groove 204, leaving the smallest most diameter between 0.325 and 0.331 inch and using an angle between 6° and 8° gives the best performance in most service pistols. The thickness of the rear head surface 202 as it relates to the distance between the rear head surface 202 and the forwardmost portion of groove surface 220 works best between 0.030 and 0.040 inch with no lead in taper. These ranges generate the most reliable rates of desired malfunctions, with the least rate of undesired stoppages that require tools to extract a stuck cartridge. Using these dimensions may incur a disadvantage in the manufacturing process as the case head exterior may be smaller than the case mouth interior and cause cases to be telescopically engaged or stuck when processed in bulk. Measures may need to be taken to avoid this to enjoy the benefits of cartridges with this relationship of case head and mouth diameter.
The .40 S&W/.357 Sig and .45 ACP cartridges react differently, allowing a larger angular deviation from about 10° up to slightly less than 90° if the depth of the rear extractor surface 218 where the extractor 24 interacts with it is between 0.0035-0.009 inch when measured at 90° from the rear head surface 202. When the width of the rear extractor surface is reduced, the angle may be closer to 90°.
It should be appreciated that the primer, propellant, and bullet enable the stoppage-inducing ammunition cartridge 200 to fire exactly like prior art ammunition cartridge 10 with the shooter experiencing a normal sense of recoil. Thus, the shooter has no warning that the stoppage-inducing ammunition cartridge has been chambered until a failure to extract malfunction is experienced when the firearm attempts to chamber another round as the firearm cycles after discharge. The rear extractor surface 218 and groove surface 220 are changed relative to the extractor groove 14 of prior art ammunition cartridge 10 to remove the lip 22, which is a flat surface the hook 26 of the extractor 24 pulls against. However, the rear extractor surface and groove surface of the stoppage-inducing ammunition cartridge 200 still permit the hook to get some purchase on the groove surface so the case 222 can be removed during the clearing process. However, the limited purchase of the hook on the grooves surface prevents the extractor from properly and completely removing the case during the violent cycling process following discharge of the stoppage-inducing ammunition cartridge 200. This limited effect of the extractor at extracting the case from a firearm chamber after discharge creates a realistic failure to extract malfunction for training purposes.
It should be appreciated that the primer, propellant, and bullet enable the stoppage-inducing ammunition cartridge 300 to fire exactly like prior art ammunition cartridge 10 with the shooter experiencing a normal sense of recoil. Thus, the shooter has no warning that the stoppage-inducing ammunition cartridge has been chambered until a failure to extract malfunction is experienced when the firearm attempts to chamber another round as the firearm cycles after discharge. The rear extractor surface 318 and groove surface 320 are changed relative to the extractor groove 14 of prior art ammunition cartridge 10 to remove the lip 22, which is a flat surface the hook 26 of the extractor 24 pulls against. However, the rear extractor surface and groove surface of the stoppage-inducing ammunition cartridge 300 still permit the hook to get some purchase on the groove surface so the case 322 can be removed during the clearing process. However, the limited purchase of the hook on the grooves surface prevents the extractor from properly and completely removing the case during the violent cycling process following discharge of the stoppage-inducing ammunition cartridge 300. This limited effect of the extractor at extracting the case from a firearm chamber after discharge creates a realistic failure to extract malfunction for training purposes.
For standard cartridges, the mouth interior on a 9 mm Luger cartridge is 0.3555-0.0030, while the head diameter is 0.394-0.010; the mouth interior on a .40 S&W cartridge is 0.4005-0.0030, while the head diameter is 0.424-0.010; and the mouth interior on a .45 ACP cartridge is 0.4520-0.0030 (w/jacketed bullet), while the head diameter is 0.480-0.010. The stoppage-inducing ammunition cartridge 400 variant for .40 S&W has a reduced exterior rear head diameter of 0.353-0.002. Similar reductions in the exterior rear head diameter are used for 9 mm Luger cartridges and .45 ACP cartridges.
It should be appreciated that the primer, propellant, and bullet enable the stoppage-inducing ammunition cartridge 400 to fire exactly like prior art ammunition cartridge 10 with the shooter experiencing a normal sense of recoil. Thus, the shooter has no warning that the stoppage-inducing ammunition cartridge has been chambered until a failure to extract malfunction is experienced when the firearm attempts to chamber another round as the firearm cycles after discharge. The rear extractor surface 418 and groove surface 420 are changed relative to the extractor groove 14 of prior art ammunition cartridge 10 to reduce the diameter of the lip 22, which is a flat surface the hook 26 of the extractor 24 pulls against. However, the rear extractor surface and groove surface of the stoppage-inducing ammunition cartridge 400 still permit the hook to get some purchase on the groove surface so the case 422 can be removed during the clearing process. However, the limited purchase of the hook on the grooves surface prevents the extractor from properly and completely removing the case during the violent cycling process following discharge of the stoppage-inducing ammunition cartridge 400. This limited effect of the extractor at extracting the case from a firearm chamber after discharge creates a realistic failure to extract malfunction for training purposes. This contrasts with a conventional cartridge having a rebated head where the head diameter is less than a cartridge diameter. In those cases, the extractor groove is formed to a depth that is enough for reliable extractor engagement.
It should be appreciated that the primer, propellant, and bullet enable the stoppage-inducing ammunition cartridge 500 to fire exactly like prior art ammunition cartridge 10 with the shooter experiencing a normal sense of recoil. Thus, the shooter has no warning that the stoppage-inducing ammunition cartridge has been chambered until a failure to extract malfunction is experienced when the firearm attempts to chamber another round as the firearm cycles after discharge. The rear extractor surface and groove surface are omitted compared to prior art ammunition cartridge 10 to remove the lip 22, which is a flat surface the hook 26 of the extractor 24 pulls against. However, as was described previously, the case 522 can be removed during the clearing process. However, the limited purchase of the hook on the circumferential extractor surface 504 prevents the extractor from properly and completely removing the case during the violent cycling process following discharge of the stoppage-inducing ammunition cartridge 500. This limited effect of the extractor at extracting the case from a firearm chamber after discharge creates a realistic failure to extract malfunction for training purposes.
It should be appreciated that the primer, propellant, and bullet enable the stoppage-inducing ammunition cartridge 600 to fire exactly like prior art ammunition cartridge 10 with the shooter experiencing a normal sense of recoil. Thus, the shooter has no warning that the stoppage-inducing ammunition cartridge has been chambered until a failure to extract malfunction is experienced when the firearm attempts to chamber another round as the firearm cycles after discharge. The rear extractor surface 618 and groove surface 620 are changed relative to the extractor groove 14 of prior art ammunition cartridge 10 to increase the diameter of the lip 22, which is a flat surface the hook 26 of the extractor 24 pulls against. However, the rear extractor surface and groove surface of the stoppage-inducing ammunition cartridge 600 still permit the hook to get some purchase on the groove surface so the case 622 can be removed during the clearing process. However, the limited purchase of the hook on the groove's surface prevents the extractor from properly and completely removing the case during the violent cycling process following discharge of the stoppage-inducing ammunition cartridge 600. This limited effect of the extractor at extracting the case from a firearm chamber after discharge creates a realistic failure to extract malfunction for training purposes.
All the embodiments of the stoppage-inducing ammunition cartridge can be manufactured from the same materials and using the same processes as prior art ammunition cartridge 10. The shapes of the cartridge case head and extractor groove are varied during manufacturing to conform to specific dimensions to create the various embodiments of the stoppage-inducing ammunition cartridge. If the rear extractor surface is inadequately angled or too deep, the case will be effectively extracted and not induce the desired stoppage.
While current embodiments of a stoppage-inducing ammunition cartridge have been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. For example, a separate groove or cut-out could be added to the area at the front of the extractor groove where the extractor groove meets the body. The additional groove would not affect the stoppage-creating performance of the stoppage-inducing cartridge as intended. Instead, the additional groove would make it easier to load the stoppage-inducing cartridges in conventional loading machines that make use of the conventional extractor groove to hold the cases in place during assembly. The additional groove would replace the traditional extractor groove on some cases to facilitate loading. With respect to the above description then, it is to be realized that the optimum dimensional relationships for the parts of the invention, to include variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention.
Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.
This application claims the benefit of U.S. Provisional Patent Application No. 62/597,574 filed on Dec. 12, 2017, entitled “STOPPAGE INDUCING CARTRIDGE,” which is hereby incorporated by reference in its entirety for all that is taught and disclosed therein.
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| Entry |
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| Number | Date | Country | |
|---|---|---|---|
| 20190178614 A1 | Jun 2019 | US |
| Number | Date | Country | |
|---|---|---|---|
| 62597574 | Dec 2017 | US |
