"One Shot, One Kill: Marines Begin Fielding New Precision Rifle Optic" 22 Feb 2021 Military.com | By Matthew Cox The Marine Corps has started fielding a new rifle optic designed to adjust for close and long-range targets for more precise shooting. Marine Corps Systems Command's Program Manager for Infantry Weapons began fielding the Squad Common Optic, or SCO, in January for the M4 and M4A1 carbines and the M27 Infantry Automatic Rifle, according to a Feb. 18 announcement. Continues at One Shot, One Kill: Marines Begin Fielding New Precision Rifle Optic