Well, this guy claimed that everyone in the Army knew all about John C. Garand and that they almost always called the rifle by his name.
He was wrong. All 4 of my uncles who fought in the infantry in WWII did and still do refer to the Garand as the "M1".
I was in a navy reserve unit on active duty in the 1970s, and everyone, including the armorers, referred to the Garand as the "M1". Everyone also referred to the .30 M1 Carbine as the "carbine".