The SIG SAUER MPX SBR delivers the full submachine-gun experience in a civilian-legal short-barreled rifle, built around SIG's short-stroke gas piston operating system — a genuine rarity in the 9mm SMG world, where most designs settle for blowback. The result is a softer-shooting, cleaner-running gun with a light bolt and minimal reciprocating mass. This configuration pairs a 4.5" barrel with a PDW-style collapsing stock for an incredibly compact envelope, and ships with a 35-round magazine where legal. As an NFA item, purchase requires ATF approval and applicable tax stamp; our team can walk you through the process.

This firearm ships to your chosen FFL dealer for transfer. Order online from Dawson Defense, an Arizona-owned licensed dealer and importer.