Aiming at the coning motion for spinning missiles, the spinning missile gyroscopic equation of mass changing in end burning was established. Both the condition of the convergence and divergence of the origine were analyzed based on Lyapunov's linear theory, and the activating region for coning motion was obtained. It is found, with the achieved analytic formula of oscillation frequency of a spinning missile, that there are three frequency characteristics for a spinning missile in flight, that is, the dampless oscillation frequency of a missile is higher than the oscillation frequency in powered-flight phase, while the oscillation frequency in powered-flight phase is higher than the oscillation frequency in maneuver flight with slight dithering canards. In the end, an explanation of the unexpected falling" phenomenon for the spinning artillery projectile was given."