McBride next fought during the Siege of Lexington on September 13–20, 1861. His men were positioned along the Missouri River and attacked the Union Army garrison on September 18 and 20, where "General McBride and his troops were specifically mentioned for their bravery and gallant service." Early in 1862 much of the Missouri State Guard force was reorganized into two Confederate brigades and commanded by Brig. Gen. Daniel M. Frost. On January 23 any remaining soldiers were put under McBride's command and renamed Missouri's 3rd Brigade of Volunteers.