Patent Application
20110016763
Not applicable.
Not applicable.
1. Field of Invention
This application generally relates to a blank cartridge and chamber for use in simulated firearms not capable of discharging projectiles.
2. Prior Art
Blank cartridges are used to simulate the visual and auditory effects of ammunition cartridges. Blank cartridges include a primed case and propellant but do not have projectiles as do ammunition cartridges. The lack of a projectile permits blank cartridges to be used safely for training, theatrical, educational, and recreational purposes.
Simulated firearms are intended as safer substitutes of actual firearms for training, educational, recreational, and theatrical purposes. Simulated firearms are intended to appear like actual firearms and produce the realistic sound and visual effects of gunfire. Simulated firearms may have magazines as do actual firearms. The essential difference of simulated firearms from actual firearms is that simulated firearms cannot discharge projectiles. This characteristic makes simulated firearms safer for many uses and can exempt the devices from significant legal restrictions controlling the sale, use, and possession of actual firearms.
Blank cartridges operate similarly to firearm cartridges in general. A blank cartridge is slidably inserted into a chamber of corresponding internal dimensions. A firearm bolt is closed, seating the cartridge upon the cartridge neck, case mouth, cartridge shoulder, or case rim. A striker is forwardly released through the bolt face to impact and detonate the primer. The resulting flash is ported through one or more flash paths to the interior of the cartridge. The propellant ignites and generates highly pressurized exhaust gases. The exhaust gases are vented from the cartridge and exit through the chamber.
A cartridge, whether blank or ammunition, may be used only in a chamber of mated physical dimensions. If the cartridge does not mate within the chamber, it will not seat and be incapable of discharging. Even minor dimensional variations can prevent a cartridge from operably seating within a chamber and may cause dangerously elevated gas pressures. These dimensional constraints restrict the cartridges that may be employed in a chamber and prevent the use of unsafe cartridges.
There are two main types of blank cartridges. The first type has exterior dimensions similar to ammunition cartridges and is intended for use in actual projectile-discharging firearms. This type of blank cartridge is thus interoperable with ammunition cartridges. An example is the 5.56×45 mm blank cartridge. This blank cartridge is interoperable with the 5.56 mm×45 mm military ammunition cartridge. The 5.56×45 mm blank cartridge vents exhaust gases in a forward direction like the related ammunition cartridge, generating realistic visual and auditory effects. This blank cartridge can cycle the action of an automatic firearm chambered for the ammunition cartridge. The disadvantage with this type of blank cartridge is that its interoperability with ammunition cartridges always risks the accidental loading and discharge of an ammunition cartridge. The inadvertent discharge of a projectile cartridge is known to cause serious damage, injury, or death.
The second type of blank cartridge is inoperable in the chamber of projectile-discharging firearms. These blank cartridges have external dimensions different from ammunition cartridges and are only operable with the mated chambers of simulated firearms. An example is the rimless 8 mm Fiocchi blank cartridge and chamber for simulated firearms. The Fiocchi blank cartridge has a flat nose which is different from the rounded bullet of a bottleneck ammunition cartridge. The Fiocchi blank cartridge and blank chamber also operate differently from ammunition cartridges and chambers. The Fiocchi cartridge is seated and detonated within the Fiocchi chamber. Instead of directing the exhaust gases in a forward direction, the Fiocchi blank cartridge ports exhaust gases laterally in a direction perpendicular to the axis of the blank cartridge. The exhaust gases are vented from the blank chamber in a similar direction lateral to the axis of the chamber. The exhaust gases are not vented through the barrel. This type of gas venting prevents a projectile from being discharged through the muzzle of the simulated firearm. However this gas venting does not create realistic visual and auditory effects. The flat nose also limits the internal capacity for propellant and restricts the volume of propellant available for visual and auditory effects. This limited propellant capacity also reduces the energy for cycling the actions of larger automatic simulated firearms. The external profile of the flat nose can cause feeding problems when employed in the magazines of automatic simulated firearms. Finally, blank cartridges adapted for this unconventional lateral porting of exhaust gases are more expensive to manufacture than other blank cartridges.
Accordingly, there are several objects and advantage of the present invention. The blank cartridge is inoperable with projectile-discharging firearms. The unique dimensions of the blank cartridge prevent it from seating and operating within ammunition chambers of projectile-discharging firearms. The crimped cartridge shoulder forms a cartridge neck which further prevents the blank cartridge from seating within an ammunition chamber. The enclosed nose allows a greater volume of propellant to be used and also improves feeding with firearm actions and magazines. The case can be manufactured from brass stock in the common 0.223 Remington or 5.56×45 mm military chamberings, thus reducing manufacturing costs.
The unique dimensions of the blank chamber it inoperable with ammunition cartridges. The chamber shoulder also forms a chamber neck which prevents its use with ammunition cartridges, particularly variants of the 0.223 Remington or 5.56×45 mm military cartridges. When employed the blank cartridge and chamber port exhaust gases in a forward direction, producing more realistic visual and auditory effects. Further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
In accordance with the invention, a blank chamber of unique dimensions, a chamber shoulder forming a chamber neck, a first body bore, a second body bore, and a third body bore which is u-shaped or partially u-shaped; and a mating blank cartridge with a base, a case wall, a cartridge shoulder forming a cartridge neck, and a nose extending from the cartridge shoulder and enclosing the cartridge.
An embodiment of the invention will now be described with reference to the following diagrammatic drawings in which:
All dimensions described herein are tolerated within certain limits as is common to cartridges and chambers generally. The tolerated dimensional limits are essential to allow the blank cartridge to seat properly within the mated chamber. If any cartridge fails to seat properly within a chamber, the firearm may fail to fire or fire out of battery, causing possible injury or death. The tolerated dimensional limits are also necessary to maintain safe chamber pressure levels. The tolerated dimensional limits of the blank cartridge and chamber of the present invention have the following tolerances except where otherwise noted: 0.X=±0.1, 0.0X=±0.01; 0.00X=±0.005; 0.000X=±0.0005.
An embodiment of the blank cartridge of the present invention is illustrated in side view in
A preferred embodiment of the chamber of the present invention is illustrated in
The manner of using the blank cartridge and chamber is similar to those in current use. The blank cartridge 7 of
From the description above, a number of advantages of my blank cartridge and chamber become evident:
(a) The blank chamber 80 is dimensionally inoperable with known lethal cartridges, such that lethal cartridges will not chamber or seat if inadvertently loaded. The combined chamber shoulder 140 and chamber 150 further prevent the seating of bottleneck ammunition cartridges derived from the 0.223 Remington and 5.56×45 mm military cartridges.
(b) Exhaust gases are released from the blank cartridge 7 and blank chamber 80 in a forward direction, producing more realistic visual and auditory effects than if ported laterally.
(c) The blank cartridge 7 is dimensionally inoperable with projectile-discharging firearms chambered for the 0.223 Remington or 5.56×45 mm military cartridges.
(d) The nose 50 provides the cartridge with an exterior shape similar to a lethal cartridge, permitting more reliable feeding from the magazine fed simulated firearms.
(e) The dimensions of the blank cartridge allow it to be manufactured from stock 0.223 Remington or 5.56×45 mm military brass yet also prevent the blank cartridge 7 from operating within 0.223 Remington or 5.56×45 mm military ammunition or firearm chambers.
Accordingly, the reader will see that, according to the invention, I have provided a blank cartridge and chamber for safer use in simulated firearms. The blank chamber is inoperable with lethal cartridges. Similarly, the blank cartridge is inoperable with projectile-discharging firearms chambered for the 223 Remington or 5.56×45 mm military cartridges. The blank cartridge and chamber port exhaust gases in a realistic forward direction. The use of a nose provides better feeding from the magazines of simulated automatic firearms. The propellant capacity added by the nose allows greater visual and auditory effects. This increased propellant capacity can also generate more energy for cycling the actions of actions of larger simulated firearms, such as machine guns.
While the above description contains many details, these should not be construed as limitations on the scope of the invention, but as exemplifications of the presently preferred embodiments thereof. Many other ramifications and variations are possible within the teachings of the invention. For example, a second circumferential crimp around the case wall 20 could be used or omitted. The cartridge shoulder 30 and cartridge neck 40 may have a diameter smaller than 0.323 inches. The nose 50 could have a maximum diameter of less than 0.320 inches. As with conventional cartridges, the blank cartridge may be composed of a metal such as brass, steel, aluminum, or other metal. Some components such as the case 18, case wall 20, cartridge shoulder 30, or nose 50 could be alternatively be composed of a non-metallic material such as a plastic as is commonly used in modern shotgun shells. The primer 8 and flash path 70 could be adapted to Boxer or Berdan type priming by using one flash path 70 as shown by
Thus the scope of the invention should be determined by the appended claims and their legal equivalents, and not by the examples given.
This is a continuation in part of application Ser. No. 11/114,494, filed 2005 Apr. 26, now abandoned, and claims the benefit of application Ser. No. 11/114,494 and provisional patent Ser. No. 60/565,440, filed 2004 Apr. 27 by the present inventor, which are incorporated hereto by reference.
| Number | Date | Country | |
|---|---|---|---|
| 60565440 | Apr 2004 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11114494 | Apr 2005 | US |
| Child | 12924425 | US |
