Results from a full-scale "smart gun" trial

The "smart gun" is an artillery concept that uses pure electrothermal (ET) energy as a means of compensating for in-bore projectile velocity variation with the goal of achieving consistent muzzle velocity. Small-scale preparatory tests (30-mm caliber) and full-scale (155-mm caliber) firings are described which demonstrate that an ET discharge can be used to augment the velocity of projectiles during their down-bore travel. The smart gun consists of three component parts: a means of measuring the progress of the projectile as it moves along the bore, a means of predicting the muzzle velocity, and a means of correcting for any predicted muzzle velocity variation. Work has progressed on the former two items and some details are highlighted here. Reports on the success in using ET energy to achieve in-bore velocity augmentation. Full-scale down-bore velocity enhancement was achieved using a 1.5-MJ "boost pulse" of ET energy at the breech approximately 3 ms after peak pressure. The pressure wave generated caught the projectile during its down-bore travel, causing the projectile to undergo a velocity increase of 13 m/s above that which would have been achieved without the boost.