US Patent 7036434 Kinetic energy projectile with in-flight extended length

A length of a rod of an axial kinetic energy projectile is increased as the projectile flies to the target. The projectile includes a nose, a rear, and a base rod. The base rod has a forward member, a rearward member, and a connection between the forward member and the rearward member which allows the forward member to move axially relative to the rearward member from a contracted position where the rod has a reduced length to an extended position where the rod has an increased length greater than the contracted length. Further, the base rod includes a locking mechanism which axially locks the forward member and the rearward member together when the forward member is moved from the contracted position to the extended position.