Dumoulin SXS Shotguns - Overview & Market Listings Dumoulin shotguns are Belgian-made side-by-side (SXS) double-barreled firearms, known for their quality craftsmanship and use in hunting and sport shooting. They are available in various calibers, barrel lengths, and conditions, from collectible antique models to modern game guns. Gun is in very good condition. The trigger guard has some small amount of rust - pictures show detail.