The M85 was primarily mounted in the cupola of the M60 series tank and in versions of the USMC AAVP-7 amphibious assault vehicle. It was not a particularly reliable machine gun, partly because of ammunition stowage and feed chute were clumsy to load.

Surprisingly, many Cold War era tankers remember it somewhat fondly, mostly because M73/M219 coax machine guns were worse.

The M73/M219 Machine Gun: Mama's Ugly Baby