The journey was delayed by storms and the loss of 60 horses due to rough treatment from the heavy seas. The unit disembarked at Fortress Monroe, remained in the vicinity for six weeks, then resumed their voyage which was further delayed by calms. The battery reached New Orleans on May 10 and remained quartered there until the beginning of June. On June 5, 1863 the unit turned their horses over to the 12th Massachusetts Battery and departed New Orleans to take part in the Siege of Port Hudson. They were assigned to operate four siege mortars, a type of heavy artillery not typically used by units of light artillery. The kept up continual fire of these guns for 31 days, along with other artillery units, until the city surrendered on July 9.