Patent ID: 7086336

Claim:
A firearm cartridge case comprising: an aft end; a relatively straight-walled body portion connected to the aft end; a shoulder connected to the body portion at a body-to-shoulder junction, wherein the body portion defines a body cavity having an interior body diameter at the body-to-shoulder junction; and a neck connected to the shoulder at a neck-to-shoulder junction and having an interior neck diameter which defines a ratio of the interior body diameter to the interior neck diameter which is in the range from about 1.8:1 to 2.3:1, wherein the interior neck diameter is sized to retain a bullet at least partially nested therein, wherein the case is sized and configured to contain a sufficient quantity of propellant such that igniting the propellant by means of a primer causes formation of a propellant plug having a diameter that is approximately the diameter of the bullet, and wherein the shoulder is connected to the neck at an angle of approximately 40 degrees or more which causes the propellant plug to shear free from unburned propellant that is disposed adjacent the relatively straight-walled body portion.