A muzzle loading firearm has a barrel with a bore on a bore axis, and has a muzzle end and a breech end. A frame is connected to the barrel, and has a breech face. The frame moves between an open position in which the breech face is away from the breech end of the barrel, and a closed position in which the breech face abuts the breech end of the barrel. A breech plug is removably attached to the barrel, and is connected to the barrel by way of interrupted, or multistart threads, or locking lugs. The breech plug may have a rear face that abuts the breech face when the frame is closed, so that a primer contained in a primer pocket in the rear of the breech plug is fully supported on all sides.
1. A muzzle loading firearm comprising:
a barrel with a bore defining a bore axis, and having a muzzle end and a breech end;
a breech element connected to the barrel, and having a breech face, the breech element being movable between an open position in which the breech face is away from the breech end of the barrel, and a closed position in which the breech face is in registration with the breech end of the barrel;
a breech plug removably attached to the barrel, the breech plug defining a primer pocket that is enclosed when the breech element is in the closed position, such that a primer in the pocket is fully supported on all sides; and
wherein the primer pocket is at least in part defined by an extractor movably connected to the breech plug.
2. A muzzle loading firearm comprising:
a barrel with a bore defining a bore axis, and having a muzzle end and a breech end;
a breech element connected to the barrel, and having a breech face, the breech element being movable between an open position in which the breech face is away from the breech end of the barrel, and a closed position in which the breech face is in registration with the breech end of the barrel;
a breech plug removably attached to the barrel, the breech plug including a pin that protrudes radially from a periphery of a flange portion of the breech plug; and
wherein the breech end of the barrel defines a breech plug chamber, the breech plug chamber having a track portion that provides a path for receiving the pin for limiting an orientation in which the plug may be installed.
3. A muzzle loading firearm comprising:
a barrel with a bore defining a bore axis, and having a muzzle end and a breech end;
a breech element connected to the barrel, and having a breech face;
the breech element being movable between an open position in which the breech face is away from the breech end of the barrel, and a closed position in which the breech face abuts the breech end of the barrel;
a breech plug removably attached to the barrel;
the breech plug defining a primer pocket and having a rear face abutting the breech face when the breech element is in the closed position; and
wherein the primer pocket is at least in part defined by an extractor movably connected to the breech plug.
4. A muzzle loading firearm comprising:
a barrel with a bore defining a bore axis, and having a muzzle end and a breech end;
a breech element connected to the barrel, and having a breech face;
the breech element being movable between an open position in which the breech face is away from the breech end of the barrel, and a closed position in which the breech face abuts the breech end of the barrel;
a breech plug removably attached to the barrel;
the breech plug defining a primer pocket and having a rear face abutting the breech face when the breech element is in the closed position and including a pin that protrudes radially from a periphery of a flange portion of the breech plug; and
wherein the breech end of the barrel defines a breech plug chamber, the breech plug chamber having a track portion that provides a path for receiving the pin for limiting an orientation in which the plug may be installed.
5. A muzzle loading firearm comprising:
a barrel with a bore defining a bore axis, and having a muzzle end and a breech end;
a breech element connected to the barrel, and having a breech face;
the breech element being movable between an open position in which the breech face is away from the breech end of the barrel, and a closed position in which the breech face abuts the breech end of the barrel;
a breech plug removably attached to the barrel;
the breech plug defining a primer pocket and having a rear face abutting the breech face when the breech element is in the closed position, the rear face of the breech plug entirely encircling the primer pocket;
a movable extractor forming part of the rear face of the breech plug; and
a slot formed in the rear face of the breech plug that extends perpendicular to the bore axis from the primer pocket.
6. The muzzle loading firearm of claim 5 , wherein:
the slot is configured so as to receive a leg portion of the extractor only when the plug is in a selected orientation and to prevent rotation of the plug when in said orientation.