He was appointed to the Colonelcy after earlier service with a regiment later re-titled the 15th of Foot. The 31st Regiment of Foot had received its numerical title in 1714 but, following the long-established practice still observed at that time by the majority of British Army infantry units, it took his name as Colonel Handasyd’s Regiment. As such, and under his command, it acquired a fine fighting reputation.

It was present at the Battle of Dettingen in 1743 when King George II (the last English monarch to lead his troops into battle in person) bestowed upon its members the nickname “Young Buffs”. Colonel Handasyd did not himself take part in that battle, being detained on duties in England. He died near Hammersmith on 27th February 1745.