On September 4, 1778, MacKinnon led his company in the Raid of Cape Sable Island, surprising the crew of an American privateer, taking and burning the ship. For his aggressive action, MacKinnon was praised highly by Brigadier General Eyre Massey. In response, one of his friends, Cpt. MacDonald, wrote to Major John Small, "McKinnon was embarrassed by the praise of the General and requested it not be inserted in the record since he only did his duty.Kim Stacy (1994). No One harms me with impunity - the History, Organization and Biographies of the 84th Highland Regiment (Royal Highland Emigrants) and Young Royal Highlanders during the Revolutionary War 1775-1784. Unpublished manuscript. p. 29" MacKinnon and his company took part in the Siege of Charleston and eventually stationed in Charleston. His company saw action around South Carolina as a detachment of the 84th at Wiggin's Hill near Augusta in 1781.
