On condition that the front body shape of the projectile is unchangeable,a formula is obtained for determining the relation between the optimum boattail angle and the supersonic flight region.

在弹丸前体外形和外界大气密度不变的条件，弹丸炮口马赫数和顶点马赫数确定旋转弹丸最佳尾锥角的方法。