Patent ID: 8434394

Claim:
In a smooth bore gun tube of a second caliber, an apparatus combinable with a rocket assisted artillery projectile of a first caliber, which is smaller than the second caliber, rendering said apparatus-rocket assisted artillery projectile combination firable from said smooth bore gun tube of said a second caliber, the apparatus comprising: an adapter for connecting to an aft end of the rocket assisted artillery projectile, the adapter including a main channel for receiving rocket exhaust, a plurality of sub-channels that lead from the main channel to an exterior of the adapter, and an ignition channel that leads from the main channel to an ignition delay disposed in the adapter; a tail boom fixed to an aft end of the adapter, the tail boom including an opening in a fore end that communicates with the ignition delay in the adapter; the tail boom containing an ignition cartridge; propellant increments on said tail boom ignited by said ignition cartridge for propelling the adapter-rocket assisted artillery projectile combination out of the smooth bore tube; and wherein gases generated by the ignition cartridge pass through the opening in the fore end to light the ignition delay; and wherein the ignition delay will subsequently ignite a rocket motor in said rocket assisted artillery projectile after said adapter-rocket assisted artillery projectile combination has exited out of the smooth bore tube.