An elongated electromagnetic railgun (1) adapted to propel a moving armature (30) through a bore (11) along the length of the railgun (1) from its breech end (21) to its muzzle end (22). The railgun (1) comprises two elongated mechanically rigid electrically conductive barrel sections (13), said sections (13) being spaced apart from each other along the length of the railgun (1). Mechanically coupled via a dielectric (18) to each barrel section (13) is an elongated current carrying rail (14) for providing electromagnetic propulsive force to the armature (30). The two rails (14) face each other across an elongated open channel, defining the bore (11). The two barrel sections (13) are electrically connected to each other at a maximum of one location of the railgun (1).