Abstract: The construction and arrangement of the projectile bearing surface interfaces rearward and forward of a recessed surface chamber of the projectile interface conjointly with the interfaces of bore wall areas segmented by recessed bore chambers which in conjunction effect the deployment/transport/dispersement/development/modulation and transformation of explosive propellant charges sequentially primed and activated rearward and forwardly of the projectile along the bore and in bore wall chambers captively converting high static gas pressure to expansively relieved dynamic propellant gas pressure directly at the projectile reducing firearm barrel recoil while energizing projectile movement along the bore in a closed-system of thermodynamic propellant energy for free flight purposes.

Abstract: A method of imparting a rotational motion to a projectile in a firearm barrel by flow of propellant gases within surfaces of the rear area of the projectile into pressure relieving chambers opening into the barrel bore along it length, each chamber allowing the propellant gases to impart an impulse to the rotational motion of the projectile, the projectile seals the bore past each chamber to prevent the escape of propellant gases so that the full volume of the gas is retained to propel the projectile until it leaves the barrel; and after the projectile has left the barrel the rear surfaces act with atmospheric air flow to increase tangential drag to reduce the effect of gyroscopic spin overstabilizing forces to provide increased range and accuracy.

Abstract: A firearm barrel is provided with a smooth bore which is widened in areas with annular grooves or pockets in the bore walls which act as propellant gas pressure relief areas. When a projectile is fired through the smooth bore, helical notches in the rear of the projectile cooperate with the gas-relief areas of the bore to allow propellant gas to flow and be expanded through the rear helicals, imparting a twist to the projectile, as the cylindric calibre proper of the projectile fills and seals the forward area of the bore proper past the widened bore areas, therefore gas is prevented from escaping past the projectile's forward end and the full volume of the gas is retained to propel the projectile forward until it has left the muzzle of the firearm barrel.