The Dual Cycle Rifle (DCR) was a 5.56x45mm NATO calibre revolver-type assault rifle that used a unique gas operation with a Webley-Fosbery-type grooved cylinder enabling 3-round bursts capable of firing 4,900 rounds per minute.
A rifle mechanism that will automatically fire, from a single barrel, a three-round burst at approximately 4,900 rounds per minute (rpm) without the use of a round counter, is disclosed. The rifle mechanism includes a cam and follower mechanism. The cam path controls the basic function of the rifle system to obtain the highest rate of fire with minimum operating rod velocities and to provide the ability to fire the three-round bursts without a round counter. The three rounds are loaded simultaneously into a chamber and the chamber is indexed to fire out each round before extraction. This eliminates the need for a full stroke cartridge handling mechanism.
This invention relates to rifle mechanisms, and more particularly to a rifle mechanism capable of providing a high rate of fire.
Presently available automatic weapons designed and developed for military and individual use generally have firing rates in the range of 500 to 1,000 shorts per minute. There are, of course, weapons mechanisms which have normal rates of fire up to 2,500 rounds per minute. As these mechanisms are pushed to higher cyclic rates, reliability and durability tend to fall off rapidly. When a round is fired in the prior art weapons, the moving elements must extract the empty case from the chamber, eject it and cock the hammer (if there is one) on the rearward stroke. The moving elements must also transfer energy to a storage device, usually a drive spring or buffer, and be brought to rest. On the forward stroke, a new round must be stripped from the magazine and chambered for firing.
For military rifle cartridges, the sequence described above requires that the moving parts have average velocity of from ten to fifteen feet per second in order to provide cyclic rates of 1,500 to 2,000 shots per minute. Peak velocities may run several times higher than the average velocity, reaching forty to sixty feet per second in most weapons. At these high velocity rates, spring surging is a very serious concern and impact loads at these high velocities are very high. These high impact velocities produce stresses which may drastically shorten parts life.
There are, of course, high-rate-of-fire mechanisms known in the art. However, these weapons are generally multi-barreled weapons such as the Gatling gun which operate reliably at rates of fire of up to 6,000 rounds per minute. These systems, because of the number of barrels and multiple bolt assemblies, are too heavy and bulky for use by the individual rifleman. High-rate-of-fire (2000 spm) rifle mechanisms that can provide a burst of three rounds or more have also been designed. Unfortunately, the current state-of-the-art requires that such weapons utilize a round counter mechanism that is connected to the trigger sear mechanism. The most successful weapon of this type (known to the inventors) utilizes a mechanism which is, for all practical purposes, as intricate as a clock mechanism. Such a mechanism is far too complicated expeditious field use and maintenance.
This invention solves the problem of obtaining a high rate of fire and a burst control mechanism with a minimum number of components.
The rifle mechanism of this invention provides a weapons system that will automatically fire, from a single barrel, a three-round burst at approximately 4,900 shots per minute. In the rifle mechanism of this invention, three rounds are loaded simultaneously into a chamber and fired at a high rate with but one push of the operating rod. At the end of the firing of three rounds, the empty cases are extracted and in the return stroke of the operating rod three more rounds are loaded and ready for the next trigger pull.
In the preferred embodiment, shown and described, the chambers are shown grouped in a cylinder which turns on its axis. The cylinder is serially indexed to fire out each round before the empty cases are extracted. This eliminates a need for a full-stroke cartridge handling mechanism. The elimination of the need for a full-stroke cartridge handling mechanism provides for a low velocity of the actuating rod, as compared to the actuating rod velocities of prior art rapid-fire rifle mechanisms.
The rifle mechanism of this invention includes a cam path formed on the surface of the cylinder which controls the basic function of the rifle system to obtain the high rate of fire with the minimum operating rod velocity.
The cam path also provided the ability to fire three rounds without a round counter. When the first round is fired, the operating rod begins its rearward movement and the cam path provides for rotation of the cylinder to place the next round in firing position. As the next round fires and the operating rod continues rearward, the cylinder rotates to the next position to fire the third and final round. After the third round is fired, the inertia of the operating rod continues to drive the follower in the cam path to rotate the cylinder to such a position that all chambers are exposed for extracting and for feeding the next three rounds. A return spring, which is compressed during the rearward operation of the operating rod, returns the operating rod for feeding and for positioning the first round in firing position. With the operating rod in its "in battery position", the weapon is again ready for firing. This single stroke of the operating rod for firing a burst of three rounds provides for a high rate of fire with but a minimum amount of movement of the components of the rifle mechanism and, therefore, a minimum amount of gun movement between shots. By minimizing the gun movement, projectile dispersion should provide for tighter target pattern per trigger pull.
It is therefore an object of this invention to provide a high rate of fire rifle mechanism.
It is another object of this invention to provide a rifle mechanism that will automatically fire, from a single barrel, a burst of rounds at a high rate. It is a further object of this invention to provide a rifle mechanism that will automatically fire, from a single barrel, a three-round burst at approximately 4,900 shots per minute.