'On the morning of the 27th May 1918 near Colincamps, our trenches were subjected to very heavy hostile shelling, and X/Medium T.M. Battery was ordered to stand to in case of S.O.S. Corporal Buchanan was in charge of a gun detachment. His gun was subjected to an intense shelling and the pit was hit several times, until at last some of the ammunition was exploded and the charges set on fire. There were large quantities of 6" bombs close handy, all of which were charged and had exploders and fuses ready fixed, but although shaken by the explosion, this NCO rushed into the burning pit and with utter disregard for his personal safety extinguished the fire. He then obtained fresh charges, and though badly burnt, had his gun in action again in a few minutes. His coolness and immediate action under heavy hostile fire set a splendid example to his detachment.'
Source: London Gazette
Date: 7 October 1918

'At Bois Grenier on the 21st February 1917 this gunner did exceptionally good work on the morning of the raid by the 2nd Auckland Batt.. The Battery was subjected to Minenwerfer and shell fire, during which the Corporal of the detachment and two gunners were wounded, and the fourth man killed. In spite of the heavy shelling, Gunner Buchanan remained serving the mortar until reinforcements arrived from another detachment. He exhibited great coolness throughout, and his conduct is worthy of recognition.'
Source: London Gazette
Date: 1 June 1917