[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/419,537, filed Oct. 21, 2002.
[0002] 1. Field of the Invention
[0003] The present invention relates to a cartridge and a chamber for a firearm, in particular a cartridge and chamber for a handgun or rifle adapted to fire a bullet with an outside diameter of about 0.223 inches (″).
[0004] 2. Description of Related Art
[0005] Prior art firearms which fire bullets with an outside diameter of about 0.223″ often require the use of a relatively large firearm with a relatively large cartridge and chamber. Specifically, the diameter of the cartridge and chamber is often greater than 0.400″ and/or the length of the cartridge is often greater than 1.000″. Also, the neck and shoulder of prior art cartridges and chambers are typically provided at such an angle that the cartridge does not feed properly from the magazine into the barrel. These problems result in a slow round. In other words, it takes a comparatively long time for the round to advance from the magazine to the barrel upon pulling the trigger. Further, the dimensions of the cartridge and chamber result in wear and tear on the firearm. For instance, upon firing, some prior art cartridges are found to peen or damage the metal on the locking lugs. In addition, the prior art chambers and cartridge are typically capable of achieving a limited bullet velocity.
[0006] A variety of cartridges and chambers for 0.223″ bullets have been proposed, all of which have one or more of the problems identified above. U.S. Pat. No. 5,033,386, issued Jul. 23, 1991 to Vatsvog, describes a composite cartridge for a 0.223 caliber high velocity rifle. The outside diameter of the Vatsvog cartridge at its widest point is 0.398″. The length and shoulder angle of the Vatsvog cartridge are not discussed.
[0007] U.S. Pat. No. 5,970,879 issued Oct. 26, 1999 and U.S. Pat. No. 6,354,221 B1 issued Mar. 12, 2002, both to Jamison, describe high-power firearm cartridges. Both Jamison patents are directed to a cartridge in a first embodiment with an overall length L of about 2.2″, a shoulder angle of approximately 35°, and a diameter D of between about 0.53 and 0.54″, and a cartridge in a second embodiment with an overall length L of about 1.7″, a shoulder angle of at least 30° but less than 40°, and most preferably approximately 35°, and a diameter D of at least about 0.45″, and preferably 0.533″. Independent claims 1 and 3 of the '879 patent are specifically limited to a cartridge with a diameter of at least 0.53″ and 0.45″, respectively.
[0008] Independent claim 2 of the '879 patent discloses a cartridge longer than 1.25″, since the claim requires a first portion having an outside diameter at a location 1.25″ from the first end. The independent claims of the '221 patent disclose similar limitations. Cartridges with a shorter length, a smaller shoulder angle, or a smaller diameter are not taught or suggested by the Jamison patents.
[0009] U.S. Pat. No. 6,293,203 By, issued Sep. 25, 2001, to Alexander et al., describes a cartridge for a 5.56 millimeter (mm) (0.224″) projectile. Although the independent claims of the Alexander patent recite a limit velocity not less than 518 meters per second (m/s), or 1,700 feet per second (fps),
[0010] None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
[0011] The present invention is directed to a cartridge and a chamber for a firearm. The firearm may be a handgun or a rifle. Specifically, the cartridge and chamber are adapted for use with a firearm adapted to fire a bullet with an outside diameter of about 0.223″ (also known as a 223 round). The cartridge comprises an axis, a neck, a shoulder, a body, and an extraction groove. The cartridge has a total length between 0.870 and 1.000″. The first body outside diameter, which is the diameter of the body at its widest point, is about 0.375″, ±0.005″. The shoulder may be formed at an angle between the body and the neck where the angle is about 28°, ±3°, with respect to the axis of the cartridge. The total length, the first body outside diameter and the shoulder angle of the cartridge of the present invention are each smaller than many prior art cartridges. Upon firing a firearm equipped with the cartridge and chamber of the present invention, the bullet is capable of reaching a velocity of greater than about 2,500 fps.
[0012] The chamber of the present invention is provided for the cartridge, described above, where the cartridge has a total length between 0.870 and 1.000″. The chamber is adapted for use with a handgun or rifle with a barrel bore adapted to fit the bullet with an outside diameter of 0.223″. The barrel bore may be provided with a region adapted to fit the ogive of the bullet. The chamber comprises an axis, a neck bore, a shoulder bore, and a body bore. The first body bore inside diameter, which is the diameter of the body bore at its widest point, is about 0.376″, ±0.005″. The shoulder bore may be formed at an angle between the body bore and the neck bore where the angle is about 28°, ±3° with respect to the axis of the chamber. The total length, first body bore outside diameter and shoulder bore angle of the chamber of the present invention are each smaller than many prior art cartridges. Upon firing a firearm equipped with the cartridge and chamber of the present invention, the bullet is capable of reaching a velocity of greater than about 2,500 fps.
[0013] Accordingly, it is a principal object of the invention to provide a cartridge for a bullet with an outside diameter of
[0014] It is another object of the invention to provide a chamber for a cartridge for a bullet with an outside diameter of about 0.223″.
[0015] It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
[0016] These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
[0017] The sole FIGURE is a side view of a cartridge and a chamber for a firearm according to the present invention.
[0018] As shown in the sole FIGURE, the present invention is directed to a cartridge
[0019] The cartridge
[0020] The body
[0021] The cartridge
[0022] The body length L
[0023] The neck
[0024] The shoulder
[0025] For the sake of comparison, a standard 9 mm handgun is capable of firing a bullet at about 1,000 fps. Upon firing a handgun provided with the cartridge
[0026] The present invention is also directed to a chamber
[0027] The barrel bore
[0028] The chamber
[0029] The body bore
[0030] The body bore length L
[0031] The neck bore
[0032] The shoulder bore
[0033] As noted above, the chamber
[0034] The cartridge
[0035] The cartridge
[0036] It is to be understood that the present invention is not limited to the sole embodiments described above, but encompasses any and all embodiments within the scope of the following claims.