USA - 90 guns per 100, 4.7 homicides per 100k Canada - 30.8 guns per 100, 0.51 homicides per 100k
So if it's just the sheer number of guns in the USA causing all of the homicides, then why is there nearly 10 times as many deaths PER GUN in the US when compared to Canada? What does the USA have that Canada doesn't?