The BM-21 is used by Russian Ultranationalists during the mission "Blackout". The Ultranationalists are using the rockets to target civilian positions and by the time of the mission have caused immense civilian casualties. The Loyalist forces operating with a British SAS team have been tasked with eliminating the Ultranationalist position, including the BM-21s. The Loyalists and SAS eliminate the BM-21s and the SAS continue with their mission to rescue an informant: Nikolai. A BM-21 also appears in mission "All In". BM-21 missiles are also mentioned in a debug string of the scrapped Call of Duty 4: Modern Warfare mission "Parabolic". It is assumed that they played a part in the mission.
The BM-21 is seen in the level "Clearing the Way", when the player takes control of Eagle. They serve as SAMs, shooting at the AC-130, downing it in two hits.