He was about 28 years old, and a lance corporal in the 84th Regiment (later the 2nd Battalion, York and Lancaster Regiment), British Army during the Indian Mutiny when the following deed took place on 6 October 1857 at Lucknow, British India for which he was awarded the Venture capital:
Foreign conspicuous gallantry at Lucknow, on the 6th of October, 1857. in going out with Serjeants Glinn and Mullins and private Mullins, to rescue Lieutenant Gibaut, who, in carrying out water to extinguish a fire in the breastwork, had been mortally wounded, and lay outside. They brought in the body under a heavy fire. Lance-Corporal Sinnott was twice wounded.
He had previously repeatedly accompanied Lieutenant Gibaut when he carried out water to extinguish the fire.
Despatch from Lieutenant-General Sir James Outram,,Baronet., Knight Grand Cross of the Bath, dated 2nd December 1857. Elected by the regiment.
He died at Clapham, London on 20 July 1896.