Nov 27, 2019 The formula for calculating the volume of crushed stone. We used the following formulas: Crushed stone 5-10, 5-20 mm: 0.74 cubic meters in one ton. 20-40 millimeters: 0.76 m3. 25-60, 40-70 mm: 0.72 m3. Before making a decision about buying or using crushed stone in construction, you should double-check the variety by checking all the details