Projectile

Abstract

A projectile includes a head portion, a middle portion and a tail portion. The middle portion is disposed between the head portion and the tail portion. A recess is defined from a terminal end of the tail portion extending into the middle portion.

What is claimed is: 
     
         1 . A projectile, comprising:
 a head portion;   a tail portion; and   a middle portion disposed between the head portion and the tail portion, wherein   an area of a terminal end of the tail portion is in the range of ½ to ⅔ of an area of a circle having a diameter the same as a diameter of the terminal end of the tail portion.   
     
     
         2 . The projectile of  claim 1 , wherein
 a recess is defined from a terminal end of the tail portion and extending into the middle portion, and   a length that the recess extends into the middle portion is in the range of L/11 to L/22 where L is a length of the projectile.   
     
     
         3 . The projectile of  claim 2 , wherein a length of the recess is in the range of (L/8 to L/2)+(L/11 to L/22). 
     
     
         4 . The projectile of  claim 1 , wherein a length of the tail portion is in the range of L/8 to L/2 where L is a length of the projectile. 
     
     
         5 . The projectile of  claim 1 , wherein
 a recess is defined from a terminal end of the tail portion and extending toward the middle portion, and   an angle of an axis of the recess relative to a center line of the projectile is in the range of −15° to +30°.   
     
     
         6 . The projectile of  claim 5 , wherein the angle of the axis of the recess relative to the center line of the projectile is in the range of −4° to +10°. 
     
     
         7 . The projectile of  claim 1 , wherein
 a recess is defined from a terminal end of the tail portion and extending toward the middle portion,   an outer surface of the tail portion forms a first angle relative to a center line of the projectile,   a surface of the recess forms a second angle relative to the center line of the projectile, and   a difference between the first angle and the second angle is in the range of 5° to 30°.   
     
     
         8 . The projectile of  claim 7 , wherein the difference between the first angle and the second angle is in the range of 10° to 20°. 
     
     
         9 . The projectile of  claim 1 , wherein the head portion includes a first region having a concave profile. 
     
     
         10 . The projectile of  claim 9 , wherein the head portion includes a second region having a concave profile disposed between the first region and the middle portion. 
     
     
         11 . A projectile, comprising:
 a head portion;   a tail portion; and   a middle portion disposed between the head portion and the tail portion, wherein   a center of gravity of the projectile is disposed between a midpoint of the projectile and a terminal end of the head portion.   
     
     
         12 . The projectile of  claim 11 , wherein the projectile includes a first core and a second core. 
     
     
         13 . The projectile of  claim 12 , wherein a length of the first core is in the range of L/5 to 3*L/4 where L is a length of the projectile. 
     
     
         14 . The projectile of  claim 12 , wherein a length of the second core is in the range of L/4 to 4*L/5 where L is a length of the projectile. 
     
     
         15 . The projectile of  claim 12 , wherein a material of the first core and a material of the second core are different. 
     
     
         16 . The projectile of  claim 12 , wherein at least one of a material of the first core and a material of the second core is non-metallic. 
     
     
         17 . The projectile of  claim 11 , wherein
 one or more recesses are respectively defined from a terminal end of the tail portion and extending toward the middle portion, and   an area of the terminal end of the tail portion is in the range of ½ to ⅔ of an area of a circle having a diameter the same as a diameter of the terminal end of the tail portion.   
     
     
         18 . The projectile of  claim 11 , wherein the head portion includes a first region having a concave profile. 
     
     
         19 . The projectile of  claim 11 , wherein
 one or more recesses are respectively defined from a terminal end of the tail portion and extending toward the middle portion, and   an angle of an axis of the recess relative to a center line of the projectile is in the range of −15° to +30°.   
     
     
         20 . The projectile of  claim 19 , wherein the angle of the axis of the recess relative to the center line of the projectile is in the range of −4° to +10°.