grease gun vs roscoe

grease gun

noun
  • A small machine gun, particularly the .45 calibre M3 used by the US in WW2. 

  • A levered device for forcing grease into machinery. 

roscoe

noun
  • A handgun, particularly a revolver. 

How often have the words grease gun and roscoe occurred in a corpus of books? (source: Google Ngram Viewer )