Here in Italy you can own guns with a special licence. To do that you have to do medical examinations (that tests that you aren't crazy

After that you have to go and register on a shooting range that gives you a brief lesson about firearms and security, they let you fire 50 .22 rounds with a revolver and 50 .22 rounds with a bolt action rifle.
After that your request goes somewere and after half a year or more you'll have your licence!

The "funny thing" is that you can own an illimited number of military and hunting guns (i have a '39 Mosin Nagant, a '43 Mauser Kar 98k, aM16A1 replica firing little pistol rounds and two hunting guns .12 cal of my grandparents), but you can only own at maximum THREE pistols and SIX sporting guns (with adjustable backsights). So you can fill your house with M16, Mosins etc, but you can only have three pistols (and sincerely I don't know the motivation for this thing).

The guns that we have are not re-chambered, they shoot the same rounds as in the past, but only with a little less power.
In the case of the pistols it's impossible to own "para bellum" rounds, because only army and police are allowed to use them.
Automatic fire guns are demilled to shoot only in semi auto mode and it's impossible to own machine guns, granades and missile launchers (of course!).
A very BAD thing is that you "can't" (but people sometimes do it) shoot anywhere except for the shooting ranges, because they can give you a certificate that proove that you have fired a certain number of rounds.
The law isn't very clear about that point because you don't have to proove nothing if you're asked by a officer, but sometimes you can have big troubles if you don't do that because no one knows how to "translate" the laws.