Patent ID: 7000524

Claim:
A method for the manufacture of a round of ammunition suitable to produce subsonic flight of a projectile to a target from a weapon fired in the semi-automatic or automatic mode and having a closed gas system for operation of the bolt of the weapon comprising the steps of forming a projectile including a metal jacket having a closed end, an open end and an internal volume, and a core comprising a discrete compact disposed within said jacket, said compact being formed from a mixture of a heavy metal powder and a light metal powder to form a self-supporting compact having first and second ends and a generally cylindrical body portion intermediate said ends, said compact having a length which is less than the full length of said jacket and leaving a portion of said jacket adjacent said open end thereof void of said compact, and thereafter infolding said portion of said jacket which is void of said compact to at least substantially close said open end of said jacket, said infolding causing at least a portion of said compact proximate said open end of said jacket to at least partially fill said infolded portion of said jacket, said projectile having a weight in excess of the weight of a lead projectile of comparable size and geometry, introducing into a cartridge case suitable for receipt in the firing chamber of the weapon and having a closed end and an open end which includes a neck portion contiguous thereto and for firing a projectile from the weapon, a quantity of gun powder to partially fill said case, disposing said projectile in said open end of said case, said projectile closing said open end of said case and extending into said case a distance of at least beyond said neck portion of said case, and with at least a portion of said projectile projecting beyond said closed end of said case, whereby said weight of said projectile and said quantity of gun powder cooperatively combine to produce gas pressure within the closed gas system of the weapon to consistently operate the bolt of the weapon and to propel said projectile from the weapon at less than sonic speed when said cartridge is fired in a weapon.