Initially Musa, who was with four men, did not even realise he was being shot at.
But Cpl Reynolds, of Dalgety Bay, in Fife, together with his spotter Lance Corporal David Hatton, worked out different factors such as wind speed and the trajectory of the bullet to hit the target. Musa, who was more than 1,500 metres away, was taken out with a single shot to the chest.
Cpl Reynolds, who has killed 32 Taliban fighters, said: “I was quite proud of that shot. It is the longest recorded kill in Afghanistan. I am going to use that fact as a chat-up line in the pub when I get back home.”