Subsonic polymeric ammunition

Abstract

The present invention provides a subsonic ammunition comprising: a primer insert comprises a top surface opposite a bottom surface, a substantially cylindrical coupling element extending away from the bottom surface forming, a primer recess in the top surface that extends toward the bottom surface, a primer flash aperture positioned in the primer recess to extend through the bottom surface, a flash aperture groove in the primer recess that extends circumferentially about the primer flash aperture, and a flange that extends circumferentially about an outer edge of the top surface; a polymeric casing body comprising a generally cylindrical hollow polymer body molded over the substantially cylindrical coupling element, into the primer flash aperture and into the flash aperture groove to form a flash hole and extending toward a mid-body coupling joint; a nose comprising a projectile aperture that extends to a neck connected to a shoulder that transitions from the projectile aperture to a nose coupler, wherein the nose coupler is connected to the mid-body coupling joint; a propellant chamber formed between the projectile aperture and the primer flash aperture; and wherein the generally cylindrical hollow polymer body comprises a thickened wall that reduce the internal volume of the propellant chamber by at least 10%, wherein the thickened wall comprises a first passage comprising a first passage comprising a first aperture having a first diameter about the diameter of the flash hole that extends to a first top surface and a second passage that extends from the first top surface toward the neck, wherein the second passage has a second diameter about the size of the projectile aperture; a primer fitted in the primer pocket; a propellant disposed in the propellant chamber; and a projectile positioned in the projectile aperture.

Dependencies are inferred from the claim text.