Its magazine was able to fold forward 90 degrees under the gun barrel, and it was fitted with a collapsible wire buttstock.
First introduced as the MP48 model in the late 1940s, the wood pistol grip and forestock were replaced in the 1950s with a polymer stock on the MP310.
The SIG MP310's use of precision castings and high quality of manufacture made it an expensive weapon to produce; this expense may have contributed to it not being widely adopted.
Switzerland: The MP310 was adopted by Swiss police forces.
Chile: In service with Chilean Armed Forces and police.