|From January 1985 Publicly Released Document
“Effectiveness of The Minuteman II Stage III Refurbishment Program”
Anyway, once you ignite solid rockets, they go until the fuel and oxidizer are depleted.
|Space Shuttle reaction control system for on orbit attitude control|
Look for the thrust termination just before the minute and a half point on this video.
Yeah. Actually rocket science is hard, but kinda fun.