Context : The QF 3-pounder Hotchkiss or in French use Canon Hotchkiss à tir rapide de 47 mm (47mm / L40) was a light 47-mm naval gun introduced in 1886 to defend against new small fast vessels such as torpedo boats, and later submarines. 
Question : In which year was the service entry date for QF 3-pounder Hotchkiss?
1886