However, senior American commanders–having experienced major logistical problems during WWII and the Korean War–insisted that a single, powerful .30 caliber cartridge be developed, capable of being used by both the new automatic rifle and the new general-purpose machine gun (GPMG) in concurrent development.Fanaticism And Conflict In The Modern Age, by Matthew Hughes & Gaynor Johnson, Frank Cass & Co, 2005 This culminated in the development of the 7.62×51mm NATO cartridge.
