Additional drillings in Marl resulted in the formation coalmines. The Department of Transport commenced geotechnical drillings and route investigations. Rarer were the drillings that used two rifled barrels and a single smoothbore barrel. It manufactures bolt-action rifles, double rifles, Drillings, and shotguns. To examine this, exploratory drillings were scheduled for April 2013. The low permeability of the sandstone prevented usual in-situ leaching from drillings. This is nearly three times as deep as preceding oceanic drillings. Four drillings were not able to go through a huge salt and gypsum layer. In 1968 test drillings reveal a significant reservoir of natural gas near the city. The company expanded producing drillings, shotguns, and over and under rifle-shotgun combinations. Two of them (46.03 of Zwillings and 46.13 of Drillings) are preserved.