An overview video by Dave's Custom Airsoft of the DS Custom L129A1 DMR AEG that they put together... "The L129A1 entered service with the British Army during the Afghan War as a way to increase range and lethality at section level. Before the L129A1 was introduced all section level weapons were 5.56mm and they were being outranged by PKM and even Lee Enfields.
The L129A1 has proven very popular and is still in service today widely used by all Army combat units.