9 millimeter cartridge casing with improved deep draw capability

An increased length 9 mm cartridge casing comprising:

• a deep drawn single piece of brass having a first portion for receiving both gun powder and a bullet, a second portion for receiving a primer charge and a transition portion disposed between said first portion and said second portion;
• said first portion having an outside diameter that continuously decreases at a constant rate from a maximum adjacent to said transition portion to an opposing end of said first portion and an inner bore that contains, in cross section along a longitudinal axis, a first linear interior portion extending from said opposing end to a first inflection point, a second linear interior portion extending from said first inflection point to a second inflection point and forming an angle, .beta., with said first linear portion of from about 175.degree. to about 179.5.degree., a third linear portion extending from said second inflection point to a third inflection point and forming an angle, .THETA., with said second linear portion of from about 172.degree. to about 179.degree., and a fourth arcuate portion extending from said third inflection point to a planar interior base that is generally perpendicular to a longitudinal axis of the cartridge, wherein the maximum thickness of said cartridge casing at said second inflection point is 0.032 inch;
• said second portion having an interior chamber to receive a primer charge;
• and
• said transition portion having an internal channel extending from said first portion to said second portion, said internal channel located rearward of said planar interior base.