My Game Name came about many years ago while playing Novalogics Delta Force on-line.
There was a sniper with a .50 Cal who was harassing everyone, I spotted him but only had an M4 and he was miles away. I found a position where I thought I may have a slim chance of shooting him, little did I know that I had been followed and was about to be knifed in the back.
The Sniper had spotted me and saw that I was about to get ganked so he wanted to take the shot first. By some happy coincidence we kinda all shot at the same time, I took out the Sniper and he shot the guy about to stab me.
Suddenly over Teamspeak there was the shout "You jammy Jock Git!!", the name has stuck ever since. For anyone over the pond in the US a Jock in the UK is a Scotsman, I am certainly not a Sportsman