Private gun ownership isn't mandatory in Switzerland. Adult males (from 19 to 34) have to do military training and keep their military weapon locked up at home. About a third of the nominally eligible males are exempted/reje cted. People who have had the training don't own the weapon they get, but t hey do control it, and using it for non-military purposes is frowned on.
Hunting is popular, and there are about 24 guns per 100 residents (so gun o wnership clearly isn't mandatory).
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No doubt Cursitor Doom is at least as far off the mark about Austria.