.50 Vickers
.50 Vickers is a 12.7 mm machine gun or machine gun.
Also recorded as Gun, Machine, .5-inch; Vickers Heavy Machine Gun; Vickers .50; Vickers .50 machine gun.
Overview
12.7 mm heavy machine gun.
In detail
It is associated with United Kingdom. The record gives 1932 as its date of establishment or first appearance.
Sources
Each source is named with the standing the house places on it, so the evidence can be weighed rather than taken on trust.
reference work · Reputable secondary · Wikipedia
“Vickers .50 machine gun”, English Wikipedia, consulted as further reading
Consult the sourcereference work · Reputable secondary · Wikidata
Wikidata, structured authority record Q4346348: .50 Vickers
Consult the source