US20050183318A1

US20050183318A1 - Muzzle loading firearm, gun barrel design, projectile system and method of using thereof

Info

Publication number: US20050183318A1
Application number: US10/755,257
Authority: US
Inventors: Kenneth McGivern
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-01-12
Filing date: 2004-01-12
Publication date: 2005-08-25

Abstract

The invention relates to a gun barrel in muzzle loading firearm with a breech portion that receives a cartridge case and a muzzle that receives a projectile and an opening that connects both. Also a gun barrel with an opening, or passage bore, that is smaller than the bore of the muzzle end of the firearm is disclosed. A firearm and method of using a firearm with this type of gun barrel is disclosed, as is a projectile system that entails a cartridge with a charge that loads from a breech end and a projectile that loads from the muzzle end of the firearm.

Description

BACKGROUND OF THE INVENTION

1. Technical Field
The invention relates generally to muzzle loading firearms wherein the breech end of the barrel is shaped to accept a blank cartridge case of the same or a different caliber than the bore of the muzzle. A gun barrel, projectile system, and method of using the same is also part of the invention.
2. Related Art
A long standing problem in the design of muzzle loading or black powder firearms is that the powder is exposed to the elements. This exposure results in degraded performance of the firearm due to powder which has been dampened or otherwise effected by the elements. Exposure to the elements is particularly a problem for hunters who are afield during inclement weather and must load their weapon during periods of rain or snow, all the while attempting to protect the powder and firing mechanisms. A related problem is that the powder charge receptacle is exposed and thus may be susceptible to inadvertent loss of part or all of the powder. To alleviate these problems, one must carry, in addition to the firearm, a complement of tools and accessories suited to keep the firearm in operable condition. These tools and accessories include loose powder in a container such as a powder horn or powder flask, loose primers, a nipple wrench, nipple picks, and breech plug tools.
Thus, a need exists for a simple and reliable improvement to muzzle loading firearms, their barrel design, and projectile systems (i.e., charge and projectile) which overcome the aforementioned, and other, deficiencies associated with the related art.

SUMMARY OF THE INVENTION

To overcome the above deficiencies, the present invention provides a muzzle loading firearm which fires a projectile having a first caliber, and which has a barrel bore shaped to accommodate the first caliber. The breech end of the firearm has a chamber which is shaped to accept a standard blank metallic cartridge case of the same or a different caliber of the projectile. The blank cartridge contains a primer and powder, but lacks a projectile. The cartridge chamber and the muzzle bore are connected by a suitably shaped opening. Upon discharge of the firearm, the powder charge from the cartridge case causes the projectile to be expelled from the muzzle.
In a first general aspect, the present invention provides a gun barrel for use in a muzzle loading firearm, said gun barrel comprising:

- a muzzle portion, characterized by a first caliber, said muzzle portion being configured to operationally receive a projectile;
- a breech portion, characterized by a second caliber, said breech portion being configured to operationally receive a cartridge case; and
- a connecting bore extending from said breech portion to said muzzle portion.

In a second general aspect, the present invention provides a firearm comprising:

In a third general aspect, the present invention provides a muzzle-end loading firearm comprising:

- a breech end configured so that a charge is loaded from said breech end; and
- a muzzle end configured so that a projectile is loaded from said muzzle end.

In a fourth general aspect, the present invention provides a substantially cylindrical gun barrel for use in a muzzle loading firearm, said gun barrel comprising:

- a muzzle end, and a breech end;
- a central bore extending from said muzzle end towards said breech end, said central bore characterized by a first caliber;
- a mounting portion adjacent said breech end, said mounting portion configured for mounting said gun barrel to a firearm receiver;
- a chamber adjacent said breech end, said chamber coaxial with said central bore, said chamber configured to operationally receive a cartridge case; and
- a passage bore adjacent and between each of said central bore and said chamber, said passage bore communicating between said central bore and said chamber, said passage bore having a smaller diameter than said central bore.

In a fifth general aspect, the present invention provides a method of increasing the reliability of a muzzle loading firearm, the method comprising:

- providing a gun barrel with a muzzle end and a breech end, said muzzle end having a central bore characterized by a first caliber, said central bore extending from said muzzle end towards said breech end;
- providing a mounting portion of said gun barrel adjacent said breech end, said mounting portion configured for mounting said gun barrel to a firearm receiver;
- providing a breech end chamber of said gun barrel adjacent said breech end, said breech end chamber coaxial with said central bore, said breech end chamber configured to operationally receive a cartridge case; and
- providing a passage bore of said gun barrel adjacent and between each of said central bore and said breech end chamber, said passage bore communicating between said central bore and said breech end chamber, said passage bore having a smaller diameter than said central bore;
- providing a stock operatively coupled to said gun barrel and said firearm receiver, said stock including a trigger assembly operatively coupled to said firearm receiver and to a firing pin assembly; and
- configuring said firing pin assembly to operatively interact with said cartridge case, when appropriate, to cause discharge of said muzzle loading firearm.

The sixth general aspect, the present invention provides a projectile system, adapted for use with a muzzle loading firearm, comprising:

- a cartridge of a first caliber containing a charge, adapted for loading in a breech end of said firearm; and
- a projectile of a second caliber, adapted for inserting in a muzzle end of a gun barrel of said firearm.

The foregoing and other features and advantages of the invention will be apparent from the following more particular description of embodiments of the invention. It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The features of the present invention will best be understood from a detailed description of the invention and an embodiment thereof selected for the purposes of illustration and shown in the accompanying drawings in which:
FIG. 1A is a side sectional view of a first type of gun barrel of the related art;
FIG. 1B is a side sectional view of a second type gun barrel of the related art;
FIG. 2 is a sectional elevational view of cartridge case of the related art;
FIG. 3A is a side sectional view of a first embodiment of a gun barrel, in accordance with the present invention;
FIG. 3B is a side sectional view of a second embodiment of a gun barrel, in accordance with the present invention;
FIG. 3C is a side sectional view of a third embodiment of a gun barrel, in accordance with the present invention;
FIG. 4A is a close-up side sectional view of a breech portion of the gun barrel shown in FIG. 3A, in accordance with the present invention;
FIG. 4B is a close-up side sectional view of a breech portion of the gun barrel shown in FIG. 3B, in accordance with the present invention;
FIG. 5A is a side sectional view of a first embodiment of a projectile system, in accordance with the present invention;
FIG. 5B is a side sectional view of a second embodiment of a projectile system, in accordance with the present invention;
FIG. 5C is a side sectional view of a third embodiment of a projectile system, in accordance with the present invention;
FIG. 6A is a side section view of a first embodiment of a gun barrel and projectile system, in accordance with the present invention;
FIG. 6B is a side section view of a second embodiment of a gun barrel and projectile system, in accordance with the present invention; and
FIG. 7 is a perspective view of a firearm with a gun barrel, in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Although certain embodiments of the present invention will be shown and described in detail, it should be understood that various changes and modifications may be made without departing from the scope of the appended claims. The scope of the present invention will in no way be limited to the number of constituting components, the materials thereof, the shapes thereof, the relative arrangement thereof, etc., and are disclosed simply as an example of an embodiment. The features and advantages of the present invention are illustrated in detail in the accompanying drawings, wherein like reference numerals refer to like elements throughout the drawings.
Referring to the drawings, and Figures IA and 1 B, in particular, which depict side sectional views of typical gun barrel with loading chambers known in the art. Both FIGS. 1A and 1B depict a gun barrel 100 with a muzzle end 104 and at the distal end, a breech end 103. Both gun barrels 100 have a bore 101.
FIG. 1A shows the gun barrel 100 that might be used in a typical “modern” breech-end loading gun barrel design, such as for a 0.308 rifle. That is a projectile “system” (not shown), which includes a cartridge case having a powder charge and a projectile, is totally loaded from the breech end 103 of the gun barrel 100 into a chamber 102 that is configured to match the shape and size of the projectile system inserted therein. Upon the firing of a weapon (not shown) with the gun barrel 100 shown, the projectile (not shown) is ejected towards the target from the muzzle end 104. In the “traditional” embodiment, the caliber of the bore 101 is smaller than that of the chamber 102. That is the cartridge case, containing a charge therein, is of larger diameter than the diameter of the projectile. The caliber of the projectile typically matches that of the bore 101, while the caliber of the actual cartridge case matches that of the chamber 102.
FIG. 1B, contrastingly, shows a gun barrel 100 that is used in a typical “modem” in-line muzzle-loading firearm, such as a black powder rifle. The gun barrel 100 has a bore 101 that has at one end a muzzle end 104 at which both the powder and projectile is loaded. At the distal end of the barrel 100 is a breech end 103 which includes a series of threads 106 which allows for the threaded insertion in the breech end 103 of a breech plug 105. The breech plug 105 includes a primer 107 opening from which the powder is activated. Upon the activation of the powder, the projectile is ejected towards the intended target.
Referring now to FIG. 2, a brief description of a cartridge case of the related art is presented. A typical cartridge case 200 may include the following elements: mouth 210, neck 220, shoulder 230, first element 240, flash hole 250, web 260, extractor groove 270, primer pocket 280, second element 290, and powder charge 295. A bullet, or projectile, (not shown) may be seated in mouth 210. In operation, a primer (not shown) is seated in the primer pocket 280. When the primer is forcefully struck by a firing pin of a firearm, the primer ignites and in turn causes the powder charge 295 to controllably explode, thus forcing a bullet (not shown) from the muzzle of the firearm. Cartridge cases such as cartridge case 200 may be found in a variety of configurations, including straight-walled versions which lack the shoulder area. Cartridge cases may also be had in a variety of sizes depending on the size or designated caliber of their corresponding bullet.
The present invention improves upon the related art and offers distinct, and numerous, advantages beyond it. The present invention may be employed with virtually any firearm, such as rifle, smoothbore musket, pistol, revolver, shotgun, grenade launcher, or the like.
FIGS. 3A, 3B, and 3C, contrastingly, depict side sectional views of three different embodiments of a gun barrel of the present invention. While all the embodiments, when integrated with a firearm, may be termed the “McGivern Muzzle-Loading Firearm”, the embodiments depicted in FIGS. 3A and 3C may be further termed a modern breech design, while the embodiment depicted in FIG. 3B may be further termed a straight wall design. Regardless of nomenclature, the gun barrels, depicted by a 10, have common elements and common purpose, yet variations in meeting that purpose.
The gun barrels 10 all have a muzzle end 15 at which the projectile (See e.g. FIGS. 5A-5C) is both loaded into and from which the projectile ejects from upon the firing of a firearm that the gun barrel 10 is part thereof. The gun barrel 10 include a bore 16 of a first diameter 30, or caliber. This bore 16 can be of any standard size caliber freely manufactured in the industry. For example, the bore 16 may be a 0.50 caliber, 0.45 caliber, 0.308 caliber, etc. Conversely, the bore 16 certainly can be of any customized, unique diameter. At the distal end of the gun barrel 10 is a breech end 11 having a breech chamber 12 of particular design and configuration. The breech chamber 12 has a second diameter 31, or caliber. The breech chamber 12 also has breech walls 13 which are adjacent to the cartridge upon its insertion into breech chamber 12. The breech chamber 12, similarly, can be configured to match and receive the shape and diameter, of standard size caliber cartridge blanks currently manufactured in the industry. Also, as with the bore 16, the breech chamber 12 can instead be of a unique, customized shape, configuration and caliber so as to match a custom charge that is placed therein. In either embodiment there is no requirement for an adaptor (not shown) or other additional elements to be located between the outside surface of a cartridge and the breech walls 13.
As stated above, the present invention allows for the muzzle end 15 loading of the projectile, while having the charge (e.g., powder within a cartridge casing) be loaded from a breech end 11 of the gun barrel 10. One way the invention achieves this capability is by configuring the breech end 11 of the gun barrel 10 so that a standard caliber cartridge casing (not shown) with powder, yet no projectile (i.e., “blank” cartridge), may fit therein. In order to prevent the gun user from improperly inserting an entire “traditional” projectile system (i.e., projectile and charge together) in the breech end 11, the present invention may configure the gun barrel 10 so that the first diameter 30 of the bore 16 is larger in diameter than the second diameter 31 of the breech chamber 12. In this manner, if the gun user were to inadvertently, for example, to insert the traditional projectile system (i.e., projectile and charge together) into the breech end 11 and into the breech chamber 12 and then fire the firearm, the firearm would harmlessly discharge. This is because the burning powder gases would pass around the ejecting projectile in the gun barrel 10 due to the larger diameter of the bore 16 than the projectile.
If for example the gun user inserts a traditional 0.308 projectile (i.e., bullet and charge) into the breech end 11 of a gun barrel 10 of the present invention in which the breech chamber 12 is configured to hold a 0.308 charge. That is the diameter of the projectile is approximately a 0.308 caliber diameter. If the user then were to fire the firearm, because the first diameter 30 is larger than the second diameter 31, although the charge would be activated, the projectile would leave the muzzle end 15 of the gun barrel 10 with little, or no, force and energy. This is because the burning powder gases initially behind and driving the projectile down the bore 16 would quickly pass around the projectile, because the first diameter 30 of the bore 16 is larger than the diameter of the projectile, rendering the projectile with no kinetic energy. This aspect of the invention, therefore, prevents the user from inadvertently attempting to use a traditional projectile system in the gun barrel 10 of the present invention. Thus, the firearm using an embodiment of the gun barrel 10 of the invention, has the added safety benefit of only having successful operation of the firearm by loading a blank charge in the breech chamber 12, while in consort loading a projectile from the muzzle end 15.
The embodiment in FIG. 3A includes a connector opening 22 located at the forward end of the breech chamber 12, before the bore 16. In this embodiment, the breech chamber 12 has multiple diameters. The connector opening 22 has a third diameter 32. In this embodiment, the connector opening 22 is a necked down portion of the gun barrel 10 wherein the third diameter 32 is smaller than second diameter 31. The connector opening 22 portion includes a cant 20 against which the shoulder portion of the cartridge rests against. The cant 20 forms a frusto-conical shaped portion of the breech chamber 12. This embodiment, for example, could be used with a blank cartridge of standard, shoulder design cartridge. Facing towards the muzzle end 15, adjacent the connector opening 22 is a stop 19. The stop 19 provides a surface against which the projectile rests upon the projectile's insertion into the bore 16. The stop 19, thus, allows the projectile to have some purchase against the gun barrel 10.
Similarly, the straight wall design depicted in FIG. 3B, includes a stop 19 against which the projectile rests upon the projectile's insertion into the bore 16. The gun barrel 10 in FIG. 3B includes a connector opening 22 between the breech chamber 12 and bore 16 or at the forward end of the breech chamber 12. The connector opening 22 has a third diameter 32. In this embodiment, the third diameter 32 has a diameter equal to the second diameter 31. That is, the breech chamber 12 in this embodiment is of uniform diameter.
FIG. 3C depicts a third embodiment of a gun barrel 10. While similar to the embodiment of FIG. 3A, this embodiment further includes threads 14 on the exterior surface of the breech chamber 12 at the breech end 11 of the gun barrel 10. The threads 14 provide one type of an attachment means for the gun barrel 10 to the rest of the firearm. Alternatively, the attachment threads 14 may be located on an interior surface of the breech chamber 12. Note further, the second diameter 31 of the breech chamber 12 in this embodiment is larger in caliber than the first diameter 30 of the bore 16.
It should be apparent to one of skill in the art, that other configurations of bore 16, breech chamber 12, and connector opening 22 are available. For example, a variation of the embodiment in FIG. 3A may alternatively have a first diameter 30 that is equal to, or even greater than, the second diameter 31. Also, the connector opening 22 could be configured so that the third diameter 32 is the same caliber as the second diameter 31. Similarly, variations of the embodiment of FIG. 3B could include a gun barrel 10 in which the third diameter 22 is smaller than the second diameter 31. Further, although not explicitly shown, any of the gun barrels 10 of the invention may further employ rifling on the interior surface of the gun barrel 10.
FIGS. 4A and 4B show close-up sectional views of the breech end 11 and breech chamber 12 portion of the gun barrel 10 embodiments depicted in FIGS. 3A and 3B, respectively. Both embodiments includes a threaded portion 14 at the breech end 11 of the barrel 10. A chamber insert 17 has matching threads 14 thereby allowing the threading attachment of the chamber insert 17 with the gun barrel 10. The interior of the chamber insert 17 forms a breech chamber 12 with breech walls 13. The inclusion of threads 14 on both the exterior surface of the chamber insert 17 and the interior surface of the gun barrel 10 allows for the facile replacement of the chamber insert 17. Thus, a gun user can readily change chamber inserts 17 for maintenance reasons and/or to change breech chamber 12 configurations (e.g., shapes, diameter(s) 31, 32, connector openings 22, etc.).
Turning to a projectile system 40 that is part of the present invention, FIGS. 5A, 5B, and 5C depict side sectional views of various embodiments. The various projectile systems 40 includes a charge 45 and a projectile 50. As discussed supra the projectile 50 is loaded into the gun barrel 10 via the muzzle end 15, while the charge 45 is loaded into the breech chamber 12 at the breech end 11 of the gun barrel 10.
The charge 45 includes a cartridge case 41 in which is explosive powder 42 of suitable composition. Powder 42 that may be employed include smokeless powder, black powder, Pyrodex® powder, pellets, black powder substitutes, or the like, or combinations thereof. The powder 42, upon its ignition by suitable means ultimately provides the explosive gases which project the projectile 50 out of the gun barrel 10.
For purposes of this invention, the term projectile 50 includes a bullet 53 (or de facto projectile) and all appurtenances attached thereto when the bullet 53 are loaded into the muzzle-end 15 of the gun barrel 10. Attached to the bullet 53 is a sabot 51. The sabot 51 protects the bullet 52 while it exits the gun barrel 10 and typically falls away harmlessly once the bullet 52 does exit. The sabot 51, typically made of a suitable, self-lubricating material, such as plastic, helps to make the loading of the bullet 53 into the gun barrel 10 easier. The configuration of the sabot 51 is such that it mates snugly with the bullet 52 and mates suitably with both a sabot mate 43 that is part of the charge 45 and adjoins the stop 19 that is between the breech chamber 12 and bore 16 (See e.g., FIGS. 3A and 3B). The sabot 51, thus, may have a stop mate surface 52 which is configured to allow the sabot 51 to fit tightly against the stop 19 upon the loading of the projectile 50 into the gun barrel 10. As depicted in FIGS. 5A-5C, there are numerous configurations for the projectile system 40, including the bullet 53, sabot 51, and sabot mate 43.
For example, FIG. 5A shows a sabot mate 43 that is convex in curvature, while the matching sabot 51 is concave in shape. The motion arrow, depicted by a “T”, shows the movement and mating positioning of both the charge 45 and projectile 50 upon the loading of both into the gun barrel 10 from either end. Similarly, FIG. 5B shows a different configuration of sabot mate 43 and sabot 51. This embodiment the sabot 51 includes a male extension, while the sabot mate 42 has a matching female receiving opening. The sabot mate 42 could be a receiving wad. The embodiment shown in FIG. 5B could be used with a shot shell or straight-walled cartridge case. Likewise, FIG. 5C has a cartridge case 41 with a leading extension that includes a receiving wad 44 that fits within, and matches, the female opening on the sabot 51.
It should be further apparent to one skilled in the art, that various calibers of breech chamber 12 and bore 16 may be employed. Matching this, various caliber of cartridge case 41 and projectile 50 can likewise be used. For example, standard diameters 30, 31 may be employed for the caliber of breech chamber 12 and bore 16, respectively. For example, the second diameter 31 may be a 0.45 caliber, while the bore 16 has a 0.50 caliber first diameter 30. In this manner, standard caliber charges 45 may be used with the present invention, as can standard caliber bullets 53. The term “standard” means, calibers of charge 45 and bullet 53 that are typically available to the gun using public. Conversely, the present invention may utilize customize caliber and configuration, as well.
FIG. 6A depicts a side sectional view of one embodiment of both a gun barrel 10 and the projectile system 40 in use within the gun barrel 10. In the embodiment shown, the charge 45 may be, for example, in a 0.45 caliber blank cartridge case 41. The bore 16 in FIG. 6 is a 0.50 caliber bore. The bullet 53 has been loaded from the muzzle end 15 of the barrel 10 to where the bullet 53 rests against the stop 19 of the chamber insert 17. The chamber insert 17 is configured to receive the cartridge case 41 which includes the powder 42 and an element 44. The element 44 may be a powder and compression plug 44 or a powder container plug 44. In the embodiment shown, the caliber of the chamber 12 is smaller than the caliber of the bore 16. Note also, that in the embodiment depicted in FIG. 6 no sabot is used. Additionally, the exterior surface of the cartridge case 41 rests against, or is adjacent to, the chamber insert 17. Thus, the cartridge case 41 is adjacent to the chamber.
FIG. 6B depicts a side sectional view of a second embodiment of both a gun barrel 10 and the projectile system 40 in use within the gun barrel 10. In the embodiment shown, the gun barrel 10 has no stops 19 on which the bullet 53 partially rests. The bullet 53, in this embodiment, with s sabot 51, has been loaded from the muzzle end 15 of the barrel 10 to where the bullet 53 and sabot 51 rest against, and mates with, an element 44 of a cartridge case 41. The cartridge case 41 which includes the powder 42 and an element 44. The element 44 may be a powder and compression plug 44 or a powder container plug 44. In the embodiment shown, the caliber of the chamber 12 is equal to the caliber of the bore 16. Additionally, the exterior surface of the cartridge case 41 rests on, or adjacent to, the chamber 12. Thus, the cartridge case 41 is adjacent to the chamber 12.
FIG. 7 depicts a perspective view of one embodiment of an entire firearm 1 employing the gun barrel 10 of the present invention. Several pieces of the firearm 1 are standard to the art including a stock 6, trigger assembly 2, sights 5, hammer 3, and the like. The gun barrel 10 is attached to the rest of the firearm 1, in this embodiment at a hinge 7, thereby allowing the user to open, via the hinge 7, and access the breech end 11 for loading of the charge 45 (see e.g., FIGS. 5A, 5B, and 5C) into the breech chamber 12. Upon closing of the gun barrel 10, denoted by motion arrow “M”, the user then may load a projectile 50 in the muzzle end 15 of the gun barrel 10. Upon the adequate mating of the projectile 50 against the charge 45 (see e.g., FIG. 6), and proper aiming, safety checks, etc., the user can then activate the firearm 1 via pulling the trigger assembly 2.
The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed or to the materials in which the form may be embodied, and many modifications and variations are possible in light of the above teaching. Such modifications and variations that may be apparent to a person skilled in the art are intended to be included within the scope of this invention as defined by the accompanying claims.

Claims

1. A gun barrel for use in a muzzle loading firearm, said gun barrel comprising:

a muzzle portion, characterized by a first caliber, said muzzle portion being configured to operationally receive a projectile;

a breech portion, characterized by a second caliber, said breech portion being configured to operationally receive a cartridge case; and

a connecting bore extending from said breech portion to said muzzle portion.

2. The gun barrel of claim 1, wherein said first caliber is greater than said second caliber.

3. The gun barrel of claim 1, wherein said second caliber is greater than or equal to said first caliber.

4. The gun barrel of claim 1, wherein at least a portion of said connecting bore is smaller than said second caliber.

5. The gun barrel of claim 1, wherein said breech portion includes a frusto-conical section.

6. The gun barrel of claim 1, wherein said breech portion has a uniform diameter.

7. The gun barrel of claim 1, wherein said breech portion is configured to operationally receive a cartridge case in a standard caliber.

8. The gun barrel of claim 1, further comprising a firearm operationally attached to said gun barrel.

9. The gun barrel of claim 1, wherein said connecting bore has a uniform diameter.

10. The gun barrel of claim 1, wherein said breech portion is configured to operationally received a cartridge case in a custom caliber.

11. The gun barrel of claim 1, wherein said breech portion is configured to be adjacent to said cartridge case.

12. A firearm comprising:

a connecting bore extending from said breech portion to said muzzle portion.

13. A muzzle-end loading firearm comprising:

a breech end configured so that a charge is loaded from said breech end; and

a muzzle end configured so that a projectile is loaded from said muzzle end.

14. The muzzle-end loading firearm of claim 13, wherein said breech end is adapted to not require a breech plug.

15. A substantially cylindrical gun barrel for use in a muzzle loading firearm, said gun barrel comprising:

a muzzle end, and a breech end;

a central bore extending from said muzzle end towards said breech end, said central bore characterized by a first caliber;

a mounting portion adjacent said breech end, said mounting portion configured for mounting said gun barrel to a firearm receiver;

a chamber adjacent said breech end, said chamber coaxial with said central bore, said chamber configured to operationally receive a cartridge case; and

a passage bore adjacent and between each of said central bore and said chamber, said passage bore communicating between said central bore and said chamber, said passage bore having a smaller diameter than said central bore.

16. The gun barrel of claim 15, wherein said central bore extends from said muzzle end to said muzzle end of said passage.

17. The gun barrel of claim 15, wherein said mounting portion comprises screw threads, said screw threads located on an outer surface of said gun barrel.

18. The gun barrel of claim 15, wherein said mounting portion comprises screw threads, said screw threads located on an inner surface of said gun barrel.

19. The gun barrel of claim 15, wherein said chamber is configured to operationally receive a cartridge case.

20. The gun barrel of claim 19, wherein said cartridge case is in a standard caliber.

21. The gun barrel of claim 19, wherein said cartridge case is in a custom caliber.

22. The gun barrel of claim 19, wherein said cartridge case is constructed of one of a metal, a plastic, and combinations thereof.

23. The gun barrel of claim 20, wherein said cartridge case is in a standard centerfire caliber.

24. The gun barrel of claim 15, wherein said central bore includes rifling upon a portion of an inner surface thereof.

25. The gun barrel of claim 15, wherein said muzzle end includes a muzzle brake therein.

26. The gun barrel of claim 15, wherein said muzzle brake is removably attached to said gun barrel.

27. The gun barrel of claim 15, wherein said cartridge case contains a powder selected from the group consisting of a smokeless powder, a black powder, a Pyrodex powder, and combinations thereof.

28. The gun barrel of claim 15, wherein said cartridge case is characterized by a shotgun caliber.

29. The gun barrel of claim 15, wherein said cartridge case contains a primer.

30. A method of increasing the reliability of a muzzle loading firearm, the method comprising:

providing a gun barrel with a muzzle end and a breech end, said muzzle end having a central bore characterized by a first caliber, said central bore extending from said muzzle end towards said breech end;

providing a mounting portion of said gun barrel adjacent said breech end, said mounting portion configured for mounting said gun barrel to a firearm receiver;

providing a breech end chamber of said gun barrel adjacent said breech end, said breech end chamber coaxial with said central bore, said breech end chamber configured to operationally receive a cartridge case; and

providing a passage bore of said gun barrel adjacent and between each of said central bore and said breech end chamber, said passage bore communicating between said central bore and said breech end chamber, said passage bore having a smaller diameter than said central bore;

providing a stock operatively coupled to said gun barrel and said firearm receiver, said stock including a trigger assembly operatively coupled to said firearm receiver and to a firing pin assembly; and

configuring said firing pin assembly to operatively interact with said cartridge case, when appropriate, to cause discharge of said muzzle loading firearm.

31. The method according to claim 30, wherein said mounting bore includes a threaded portion.

32. A projectile system, adapted for use with a muzzle loading firearm, comprising:

a cartridge of a first caliber containing a charge, adapted for loading in a breech end of said firearm; and

a projectile of a second caliber, adapted for inserting in a muzzle end of a gun barrel of said firearm.

33. The projectile system of claim 32, wherein said cartridge comprises a standard caliber cartridge case.

34. The projectile system of claim 32, wherein said projectile includes a sabot.

35. The projectile system of claim 32, wherein a first portion of said cartridge adjoins a second portion of said projectile.

36. The projectile system of claim 32, wherein said first caliber is smaller than said second caliber.

37. The projectile system of claim 32, wherein said first caliber is equal to said second caliber.

38. The projectile system of claim 32, wherein an exterior surface of said cartridge is adapted to be adjacent to a portion of said breech end.