gunnery vs heavy stuff

gunnery

noun
  • A place where guns are tested, or where people are trained in their use. 

  • The firing of guns. 

  • The science of guns and gunfire, including aspects of bullet flight and impact. 

  • The design and manufacture of guns, particularly those of a large caliber. 

heavy stuff

How often have the words gunnery and heavy stuff occurred in a corpus of books? (source: Google Ngram Viewer )