The Gustloff Volkssturmgewehr is constructed rather like many semi-automatic pistols, it has a casing and spring around the barrel; the whole casing recoils backward. The breech block, with firing pin and extractor, is pinned to the back end of the barrel casing. The rear end of the gun does not recoil and has the hammer, sear and trigger built into it. Gas coming from four vents, near the end of the barrel, holds the bolt closed till the gas pressure drops to a safe level. Some selective fire Gustloff Volkssturmgewehrs were made.