>>6201181 (lb)
VAW-120 (Norfolk) are the Greyhawks. VRC-30 (North Island with detachments to CVWs) is west coast
Looking at flash supressor and barrel I go with Soviet originated (1971) NSV 12.7x108mm (.50 cal)
More pics, nicknamed "dashika"
Those things can be found in the beds of little Toyota trucks from Libya to Lebanon to Syria and Afghanistan
I'm gonna say being tailgated in traffic is not a problem