Some trigger time behind the Magpul/Bushmaster ACR. This was filmed at a recent Magpul Dynamics Carbine Class where Drake from Magpul shot an ACR for the entire class. This last string of fire by myself, drake, and John E. from Aimpoint was the tail end of a 1400+round firing schedule all under 15minutes..

The song is "Bury me in smoke" by Down (less info)