Here are some interesting shooting-stats. Since the stats are per capita, the size of the country is moot, although the method of data collection may vary from nation-to-nation: There were 27% more casualties per capita from mass public shootings in the European Union than the United States from 2009-15: https://crimeresearch.org/wp-content/uploads/2015/06/Screen-Shot-2017-11-01-at-Wednesday-November-1-12.30-AM.png Top 10 countries for mass shootings per capita: https://crimeresearch.org/wp-content/uploads/2015/06/Screen-Shot-2016-04-05-at-Tuesday-April-5-1.05-AM.png Full article: https://crimeresearch.org/2015/06/comparing-death-rates-from-mass-public-shootings-in-the-us-and-europe/ Editorial https://www.investors.com/politics/editorials/sorry-despite-gun-control-advocates-claims-u-s-isnt-the-worst-country-for-mass-shootings/
It should be noted that Norway is only in the top spot because it is a small country. Their top spot comes from one mass shooting that killed 77 people in 2011. This would be called an outlier. As for overall gun death rates, the U.S. is in the same category as developing nations. https://www.cbsnews.com/news/how-u-s-gun-deaths-compare-to-other-countries/ https://www.npr.org/sections/goatsandsoda/2017/11/06/562323131/gun-violence-comparing-the-u-s-with-other-countries