Abstract: Base separation of cast explosives in projectiles is prevented by means of resilient device, such as a spring washer, positioned between the bottom of the fuzewell cavity in the cast explosive and the bottom of the fuzewell liner threadedly secured to the projectile. By tightening the liner, the spring washer is compressed, causing it to apply a force upward on the liner and downward on the cast explosive toward the base of the projectile, thereby allowing the cast explosive to move in response to thermal changes while maintaining it in contact with the projectile base at all times.