Subsonic cartridge for gas-operated automatic and semiautomatic weapons

Abstract

A subsonic cartridge that enables a conventional automatic or semiautomatic weapon to fire a projectile at a subsonic velocity and cycle the weapon to eject the spent cartridge case, without the sonic report characteristic of supersonic projectile velocities. The cartridge includes a case having a tubular shape with an open end oppositely disposed head, and a bore therebetween. The head of the case includes a primer cavity, a web separating the primer cavity from the bore, and a flash hole through the web. A primer is stored within the primer cavity, and projectile is disposed within the bore so as to close the open end of the cartridge case. A charge cavity is delimited within the bore between the web and the projectile. The charge cavity is sized and shaped to contain a limited amount of propellant charge that propels the projectile from the cartridge case at a subsonic speed.

What is claimed is:  
     
         1 . A cartridge loaded in a gas-operated weapon selected from the group consisting of gas operated automatic and semiautomatic weapons, the cartridge comprising: 
 a cartridge case having a tubular shape with an open end, and oppositely disposed head, and a bore therebetween, the head having a primer cavity, a web separating the primer cavity from the bore, and a flash hole through the web;    a primer stored within said primer cavity;    a projectile disposed within the bore so as to close the open end of the cartridge case, the projectile having a weight of about 100 grains or more;    a charge cavity delimited within the bore between the web and the projectile; and    a propellant charge contained within the charge cavity in an amount sufficient to propel the projectile from the cartridge case at a subsonic speed and to recycle the weapon.    
     
     
         2 . A cartridge according to  claim 1 , wherein the cartridge is a .223 caliber, and the charge cavity is sized to accommodate about 14 grains of the propellant charge.  
     
     
         3 . A cartridge according to  claim 1 , wherein the projectile has a weight of up to about 130 grains.  
     
     
         4 . A cartridge according to  claim 1 , wherein the propellant charge completely fills the charge cavity.  
     
     
         5 . A cartridge according to  claim 1 , wherein the cartridge is a .308 caliber, the projectile weighs about 180 to about 300 grains, and the charge cavity is sized to accommodate about 14 to about 18 grains of the propellant charge.  
     
     
         6 . A cartridge according to  claim 5 , wherein the propellant charge completely fills the charge cavity.  
     
     
         7 . A cartridge according to  claim 1 , wherein the projectile has a specific gravity of greater than 11.7.  
     
     
         8 . A cartridge according to  claim 1 , wherein the projectile has a caliber of from .22 to .50.  
     
     
         9 . A cartridge according to  claim 1 , wherein the weapon has a barrel length of about 10 to about 16 inches.  
     
     
         10 . A cartridge according to  claim 1 , wherein said projectile comprises at least one recess circumventing said projectile.  
     
     
         11 . A cartridge according to  claim 10  wherein said projectile comprises at least one ring adjacent to said recess.  
     
     
         12 . A cartridge according to  claim 11  wherein said projectile comprises three recesses and three rings.  
     
     
         13 . A cartridge according to  claim 11  wherein said ring is at least approximately 0.05 inches to no more than approximately 0.13 inches in width.  
     
     
         14 . A cartridge according to  claim 11  wherein said recess has a depth of at least approximately 0.003 inches to no more than approximately 0.010 inches.  
     
     
         15 . A cartridge according to  claim 14  wherein said depth is no more than approximately 0.006 inches.  
     
     
         16 . A cartridge according to  claim 12  wherein said projectile is at least approximately 114 grains to no more than approximately 135 grains.  
     
     
         17 . A cartridge according to  claim 16  wherein said projectile is approximately 123 grains.  
     
     
         18 . A .223 caliber cartridge loaded in a recycling weapon having a gas-operated reciprocating bolt, the cartridge comprising: 
 a cartridge case having a tubular shape with an open end, an oppositely disposed head, and a bore therebetween, the head having a primer cavity, a web separating the primer cavity from the bore, and a flash hole through the web;    a primer stored within the primer cavity;    a projectile disposed within the bore so as to close the open end of the cartridge case, the projectile having a weight of about 130 grains;    a charge cavity delimited within the bore between the web and the projectile; and    about 14 grains of propellant charge that completely fills the charge cavity, the propellant charge within the charge cavity being an amount sufficient to propel the projectile from the cartridge case at a subsonic speed and to recycle the reciprocating bolt of the weapon.    
     
     
         19 . A .223 caliber cartridge according to  claim 18 , wherein the recycling weapon is chosen from the group consisting of gas operated automatic and semiautomatic weapons.  
     
     
         20 . A .223 caliber cartridge according to  claim 19 , wherein the weapon has a barrel length of about 10 to about 16 inches, and the amount of the propellant charge in the charge cavity is sufficient to procedure a pressure of about 45,000 psi to 51,000 psi when ignited to propel the projectile from the cartridge case.  
     
     
         21 . A process of firing a cartridge from a gas-operated automatic or semiautomatic weapon, the process comprising the steps of: 
 providing a cartridge comprising: 
 a cartridge case having a tubular shape with an open end, an oppositely disposed head, and a bore therebewteen, the head having a primer cavity, a web separating the primer cavity from the bore, and a flash hole through the web;  
 a primer stored within the primer cavity;  
 a projectile disposed within the bore so as to close the open end of the cartridge case;  
 a charge cavity delimited within the bore between the web and the projectile; and  
 a propellant charge contained within the charge cavity in an amount sufficient to propel the projectile from the cartridge case at a subsonic speed;  
 loading the cartridge in a gas-operated weapon chosen from the group consisting of automatic and semiautomatic weapons having a reciprocating bolt; and then  
 firing the weapon by igniting the propellant charge, the propellant charge producing a chamber pressure sufficient to propel the projectile from the cartridge case at a subsonic speed and to recycle the reciprocating bolt of the weapon.  
   
     
     
         22 . A process according to  claim 21 , wherein the charge cavity has a noncylindrical shape.  
     
     
         23 . A process according to  claim 21 , wherein the charge cavity has a tapered shape.  
     
     
         24 . A process according to a  claim 21 , wherein the charge cavity has a uniformly and continuously tapered shape.  
     
     
         25 . A process according to  claim 21 , wherein the cartridge is a .223 caliber, the projectile weighs at least 100 grains, and the charge cavity is sized to accommodate not more than 14 grains of the propellant charge.  
     
     
         26 . A process according to  claim 25 , wherein the propellant charge completely fills the charge cavity.  
     
     
         27 . A process according to  claim 21 , wherein the cartridge is a .308 caliber, the projectile weighs about 180 to about 300 grains, and the charge cavity is sized to accommodate about 14 to about 18 grains of the propellant charge.  
     
     
         28 . A process according to  claim 27 , wherein the propellant charge completely fills the charge cavity.  
     
     
         29 . A process according to  claim 21 , wherein the projectile has a specific gravity of greater than 11.0.  
     
     
         30 . A process according to  claim 21 , wherein the projectile has a caliber of from .22 to .50.  
     
     
         31 . A process according to  claim 21 , wherein the weapon has a barrel length of about 10 to about 20 inches.  
     
     
         32 . A process according to  claim 21 , wherein the cartridge is a .223 caliber, the projectile weights at least 100 grains, and the amount of the propellant charge present in the charge cavity is sufficient to produce a pressure of about 45,000 psi to 51,000 psi when ignited to propel the projectile from the cartridge case.