The main British sniper rifle of World War Two, and arguably one of the best looking military sniper rifles of all time, the No4 MkI (T) was something the British military knew they would want even before the No4 MkI rifle had gone into real production. The first No4 snipers were built on leftover trials rifles from Enfield, and the pattern was formally introduced in February of 1942. First use was in North Africa, but the fighting there was not really suited to sniper rifles, and the weapon’s practical combat debut was in Italy in 1943.

The No4 MkI (T) was a conversion of a standard No4 MkI rifle, using examples chosen for particular good accuracy. They were sent to Holland & Holland to have scope mount bases added and No32 telescopic sights fitted (along with cheek risers on the stocks and having the battle sight aperture ground off to allow room for the scope bell). Between 23,000 and 26,000 were made during the war, and they would continue to be used in the British military for decades, including later conversion into 7.62mm NATO L42A1 rifles.