The Swiss army has long been a militia trained and structured to rapidly respond against foreign aggression. Swiss males grow up expecting to undergo basic military training, usually at age 20 in the Rekrutenschule (German for "recruit school"), the initial boot camp, after which Swiss men remain part of the "militia" in reserve capacity until age 30 (age 34 for officers). Each such individual is required to keep his army-issued personal weapon (the 5.56x45mm Sig 550 rifle for enlisted personnel or the SIG 510 rifle and/or the 9mm SIG-Sauer P220 semi-automatic pistol for officers, medical and postal personnel) at home with a specified personal retention quantity of government-issued personal ammunition (50 rounds 5.56 mm / 48 rounds 9mm), which is sealed and inspected regularly to ensure that no unauthorized use takes place. The ammunition are intended for use while traveling to the army barracks in case of invasion.

When their period of service has ended, militiamen have the choice of keeping their personal weapon and other selected items of their equipment. In this case of retention, the rifle is sent to the weapons factory where the fully automatic function is removed; the rifle is then returned to the discharged owner. The rifle is then a semi-automatic or self-loading rifle.