Sub-mass projectile for a firearm

An ammunition system for a standard, unmodified firearm, comprising:

• a) a sub-mass projectile having a relatively lower mass than a standard projectile for the standard, unmodified firearm, the sub-mass projectile further comprising:
• i) a nose disposed on a forward end of the sub-mass projectile;
• ii) a base disposed on a rearward end of the sub-mass projectile;
• iii) a shoulder disposed between the nose and the base;
• iv) a sidewall extending cylindrically between the shoulder and the base;
• v) a selectably sized substantially smooth continuous bearing surface associated with at least a portion of the sidewall, the smooth continuous bearing surface having a substantially uniform diameter from the shoulder to the base, the diameter being relatively larger than an outer diameter of a standard size and mass projectile for the firearm, the diameter size being selected to engage with the standard, unmodified firearm when the standard, unmodified firearm is discharged to create a resistive force on the standard, unmodified firearm and to facilitate a buildup of a backpressure within the standard, unmodified firearm on the sub-mass projectile, the resistive force and backpressure having sufficient magnitude to determine an operational performance characteristic of the sub-mass projectile as the projectile exits a barrel of the standard, unmodified firearm;
• b) a standard cartridge sized and shaped according to a standard cartridge size for the standard, unmodified firearm, and having an outer diameter relatively larger than the bearing surface of the sub-mass projectile, the standard cartridge being disposable around the bearing surface of the sub-mass projectile;
• and
• c) an energetic material disposed in the standard cartridge adjacent the base of the sub-mass projectile, the energetic material forming a charge for the standard, unmodified firearm.

A firearm system, comprising:

• a) a standard, unmodified firearm configured to fire standard size and mass projectiles per a pre-determined caliber of the firearm, the standard, unmodified firearm further comprising:
• i) a standard, unmodified chamber sized and shaped to receive standard size and mass projectiles;
• and
• ii) a standard, unmodified barrel configured to receive and discharge standard size and mass projectiles;
• b) an ammunition system operably engageable with the standard, unmodified firearm including a sub-mass projectile, comprising:
• i) a deformable substantially nonmetal core having a relatively lower mass than a standard projectile for the standard, unmodified firearm;
• ii) a substantially smooth uniform bearing surface associated with the core and having a relatively larger outer diameter than an outer diameter of a standard projectile for the standard, unmodified firearm;
• and
• iii) a standard cartridge sized and shaped to the caliber of the standard, unmodified firearm and the core being disposable within the standard cartridge with an outer diameter relatively larger than the outer diameter associated with the core;
• iv) an energetic material disposed in the standard cartridge near the core, the energetic material forming a charge for the standard, unmodified firearm to propel and discharge the core from the firearm;
• and
• c) the bearing surface being sized and shaped to increase resistive forces between the sub-mass projectile and the standard, unmodified barrel, and to seal the standard, unmodified barrel to allow pressure from the charge to increase in the standard, unmodified chamber until the pressure overcomes the resistive forces and the sub-mass projectile is expelled from the standard, unmodified firearm.