Polymer ammunition having a projectile made by metal injection molding

An ammunition having a metal injection molded projectile and a polymer cartridge case comprising:

• a polymer ammunition cartridge comprising
• a primer insert comprising a top surface opposite a bottom surface,
• a primer recess extending into the top surface toward the bottom surface,
• a flash aperture positioned in the primer recess and extending through the bottom surface;
• a groove positioned inside the primer recess around the flash aperture and
• a coupler extending away from the bottom surface;
• a mid-body molded from a mid-body coupler over the coupler and into the flash aperture to from a flash hole;
• a nose portion comprising a nose coupler connected to the mid-body coupler and extending to a projectile aperture;
• a propellant chamber formed between the projectile aperture and the flash hole;
• a primer inserted into the primer recess;
• a propellant at least partially filling the propellant chamber;
• and
• a metal injection molded projectile frictionally fitted in the projectile aperture, wherein the metal injection molded projectile comprises a nose extending essentially symmetrically to a shoulder, and an essentially cylindrical bearing surface extending from the shoulder to a base.