Got to be the L1A1 SLR.
Standard issue British Army rifle from the 70s and 80s. Will also be familiar to any Aussies and Canadians. Beautifully made, robust and accurate.
Will never forget my first day at the range as a 17 yr old recruit....
'Here is your Slr, the British Army unlike our American cousins do not require an automatic rifle. You will be trained to be accurate....'