But if you choose all countries,
Murders with firearms, per capita.
http://www.nationmaster.com/graph/cri_mur_wit_fir_percap-crime-murders-firearms-per-capita#1 South Africa: 0.719782 per 1,000 people
#2 Colombia: 0.509801 per 1,000 people
#3 Thailand: 0.312093 per 1,000 people
#4 Zimbabwe: 0.0491736 per 1,000 people
#5 Mexico: 0.0337938 per 1,000 people
#6 Belarus: 0.0321359 per 1,000 people
#7 Costa Rica: 0.0313745 per 1,000 people
#8 United States: 0.0279271 per 1,000 people
#9 Uruguay: 0.0245902 per 1,000 people
#10 Lithuania: 0.0230748 per 1,000 people
Murders per capita
http://www.nationmaster.com/graph/cri_mur_percap-crime-murders-per-capita#1 Colombia: 0.617847 per 1,000 people
#2 South Africa: 0.496008 per 1,000 people
#3 Jamaica: 0.324196 per 1,000 people
#4 Venezuela: 0.316138 per 1,000 people
#5 Russia: 0.201534 per 1,000 people
#6 Mexico: 0.130213 per 1,000 people
#7 Estonia: 0.107277 per 1,000 people
#8 Latvia: 0.10393 per 1,000 people
#9 Lithuania: 0.102863 per 1,000 people
#10 Belarus: 0.0983495 per 1,000 people
#11 Ukraine: 0.094006 per 1,000 people
#12 Papua New Guinea: 0.0838593 per 1,000 people
#13 Kyrgyzstan: 0.0802565 per 1,000 people
#14 Thailand: 0.0800798 per 1,000 people
#15 Moldova: 0.0781145 per 1,000 people
#16 Zimbabwe: 0.0749938 per 1,000 people
#17 Seychelles: 0.0739025 per 1,000 people
#18 Zambia: 0.070769 per 1,000 people
#19 Costa Rica: 0.061006 per 1,000 people
#20 Poland: 0.0562789 per 1,000 people
#21 Georgia: 0.0511011 per 1,000 people
#22 Uruguay: 0.045082 per 1,000 people
#23 Bulgaria: 0.0445638 per 1,000 people
#24 United States: 0.042802 per 1,000 people