Patent Application
20100064567
The present invention relates generally to a breech plug and more particularly to a breech plug with an outwardly extending ignition stem.
Breech plugs are well-known within the art for use with muzzleloading firearms. Generally, breech plugs are threadably received within the breech end of the barrel and have a nipple for receiving a percussion element. When struck, the explosive material within the percussion element is compressed between the shell of the percussion element and the nipple's anvil igniting a primary flash that is directed through a flash chamber in the breech plug to a flash port where the primary flash ignites a powder charge or propellant.
Much effort has been directed to improving the ignition of the firearm through directing and controlling the primary flash. Advancements in the prior art have taught that ignition characteristics are improved if the primary flash occurs in a relatively large diameter flash chamber and is then focused into a small diameter flash port. One problem with these conventional breech plugs is that the plug limits the area of exposure at the base of the propellant that is exposed to the primary flash during ignition. This results in slower ignition, velocity and lock time, and the propellant burns unevenly within the barrel which also affects performance.
Stems have been used in the past to ignite the propellant further within the breech end of the barrel. For example, see U.S. Pat. No. 21,802 by Schenkl. These stems tend to limit the amount of propellant that surrounds them and do not adjust the diameter of the flash chamber and flash port to increase velocity.
It is therefore a general objective of the present invention to provide an improved breech plug for a muzzleloading rifle.
Another objective of the present invention is to provide a breech plug that improves the ignition of the propellant.
Another objective of the present invention is to provide a breech plug that provides a more even burn of the propellant within the barrel.
Another objective of the present invention is to provide a breech plug that causes faster ignition, greater velocity, and increased lock time.
These and other objectives will be apparent to those skilled in the art.
A breech plug for use with a muzzleloading firearm includes a nipple for receipt of a percussion element, a center cylindrical body adapted to be received within the breech end of the barrel of a muzzleloading loading firearm, a stem with a length and a constant uniform diameter, and a flash bore extending longitudinally through the nipple, cylindrical body and stem. The stem and the nipple are attached coaxially and longitudinally to opposite ends of the cylindrical body. The stem is adapted to fit within the barrel of the muzzleloading firearm such that a chamber is created between the stem, the cylindrical body, and the barrel. Additionally, the stem is adapted such that in use propellant powder may reside within the chamber around the stem and also beyond the distal end of the stem.
Referring to the drawings, the present invention is described in reference to a muzzleloading firearm by example only. It is contemplated that the improved breech plug can also be used in other firearms and apparatus.
Referring to
The second end 26 has an attached stem 32 that is of generally uniform diameter and is coaxial to the cylindrical body 12. The stem 32 may be attached in any conventional manner to the body 12 including molded thereto. The stem 32 has a length and an outside diameter that is less than the inner diameter 33 of the axial bore 20 of the barrel 16 such that an open generally cylindrical cavity 34 is formed as defined on a first side by the inner diameter 33 of the bore 20, on a second side by the outside diameter of the stem 32, and on a bottom end 36 as defined by the second end 26 of the cylindrical body 12 abutting the inside diameter of the bore 20 and the outside diameter of the stem 32. Where the breech plug of the present invention is adapted for use within a conventional muzzleloading rifle, the axial length of the stem 32 is preferred to be 3.2 cm or 1ΒΌ inches.
The nipple 28, the cylindrical body 12, and the stem 32 are coaxial to each other and have a coaxial flash bore 38 of a certain diameter that runs therethrough. The flash bore 38 may be of generally constant diameter. Preferably, the flash bore 38 will be of a larger diameter at the nipple 28 and through the first end 24 and into the cylindrical body 12 and will transition to a smaller diameter within the stem 32.
In use, the breech plug 10 is operably connected to the barrel 16 of a muzzleloading firearm by threadably attaching the plug within the breech end 18, with the stem 32 residing within the barrel 16 and the nipple 28 residing outside the barrel 16.
A muzzleloading firearm is conventionally loaded by inserting propellant powder 46 and a ball 48 into the barrel 16 and ramming the powder 46 and ball 48 into the barrel 16 and against the breech plug 10. In use, the breech plug of the present invention will permit powder to reside both within the cavity 34 and beyond the end of the stem 32, with the ball 48 residing within the barrel 16 with a portion of powder 46 located between the ball 48 and the stem 32.
The muzzleloading firearm is further prepared by accessing the nipple 28 of the breech plug and applying a percussion element 30 thereto. Finally, the firearm is prepared for firing by cocking a firing pin, not shown, or a hammer element, not shown.
Once the firearm is prepared, it is fired in a conventional manner by pulling a trigger, not shown, thereby causing a firing pin, not shown, to strike the percussion element 30. The struck percussion element 30 produces a flame and hot gases, which travel through the flash bore 38 exiting the stem 32 and into the powder 46, thereby igniting the powder 46. Once ignited, the powder 46 will burn causing rapid expansion of hot gases that propel the ball 48 out of the barrel 12.
A conventional breech plug does not have a stem 32 and will ignite the powder at or near the end of the powder charge, which inefficiently burns the expanding and moving powder as the bullet is compelled down the barrel. In contrast, the breech plug of the present invention ignites the powder 46 in a central location or forward position which causes the powder 46 to burn forward toward the ball 48, while simultaneously burning rearward toward the base of the cylindrical cavity 34. Expansion from the ignited powder produce equal and opposite forces to those which propel the ball 48 down the barrel 16 to also compress against the powder 46 that resides within the cylindrical cavity 34. The result is that the powder 26 burns in two opposite directions simultaneously, thereby compressing and efficiently burning the powder 46 within the barrel 16.
Accordingly, as can be seen from the preceding disclosure, the breech plug meets its objectives by providing a powder burn that results in greater efficiency, muzzle velocity, consistency of firing, and resulting greater accuracy.
The foregoing description is set forth in a detailed manner, but it is to be understood that various modifications of detail, rearrangement, and multiplication of parts might be resorted to without departing from its spirit, essence, or scope.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10428792 | May 2003 | US |
| Child | 11756743 | US |
