Every healthy 18 year old Swiss male living in Switzerland is conscripted and has to go through basic army training (RS, Rekrutenschule) that takes 18 or 21 weeks. After the basic training every year soldiers have to go on a three weeks repetitions course (WK, Wiederholungskurse).
Nowadays men who for some personal reason don’t want to join the Swiss armed forces have the option of serving with a longer civil service (serving in old people’s homes and hospitals etc). I remember the days when we were drafted, people refusing to join had to go to prison.
Women are free to join the ranks too. Their proportion is not big, but there are ladies serving in the same troops along with the guys.
The army weapons have to be practiced at least once a year at the official shooting ranges.
After having served a certain number of days and having reaching a certain age the soldiers are taken out of service. Many would opt to keep their weapons.
People keep their army weapons at home. The bolt has to be kept separately and should be locked away.
Switzerland has quite a liberal weapons law. It is relatively easy to buy a gun. There are around 2.3 to 4.5 million weapons privately owned. In that aspect Switzerland is probably not lagging far behind the US. However it is quite amazing that firearms are relatively rarely used to commit crimes. Unfortunately weapons are often used in suicides. Between 1996 and 2005 over 40% of suicides were committed with army weapons.