A sampling device for sampling granular material in an at least partly enclosed space, the device comprising: a sampling head, which comprises a bore part 112), means for linearly moving the sampling head into the material and out of the material, means for producing a rotary movement for the bore part by rotating the bore part, and wherein the sampling head is adapted to be placed in the material with the tip portion of the sampling head first as the bore part is drilling into the material, and wherein the sampling head is open, like the tip portion, on at least one second point so that the material granules in mechanical contact with the bore part may become replaced as the bore part is drilling into the material, characterized in that the bore part is additionally adapted to rotate while the sampling head is off the material to empty the sampling head and to collect a partial sample to a sample collector of the sampling device from the material removed from the sampling head, the sample collector adapted to cooperate with the sampling head boring the samples, and in that the sample collector comprises a tank adapted and dimensioned to store a plurality of partial samples out of the samples bored by the sampling head, and an adjustment member (214, 216), which is adapted to adjust the volume of a sample section of the tank, the sample section adapted to collect the partial samples, so that there is room in the sample section substantially only for the amount of a first partial sample of a first sample, the adjustment member (214, 216) additionally adapted to increase the volume of the sample section, after the collection of the first partial sample, by an amount corresponding to a volume of a second partial sample of a second sample such that both the first and second partial samples fit in the sample section. a sampling head, which comprises a bore part 112), means for linearly moving the sampling head into the material and out of the material, means for producing a rotary movement for the bore part by rotating the bore part, and wherein the sampling head is adapted to be placed in the material with the tip portion of the sampling head first as the bore part is drilling into the material, and wherein the sampling head is open, like the tip portion, on at least one second point so that the material granules in mechanical contact with the bore part may become replaced as the bore part is drilling into the material, characterized in that the bore part is additionally adapted to rotate while the sampling head is off the material to empty the sampling head and to collect a partial sample to a sample collector of the sampling device from the material removed from the sampling head, the sample collector adapted to cooperate with the sampling head boring the samples, and in that the sample collector comprises a tank adapted and dimensioned to store a plurality of partial samples out of the samples bored by the sampling head, and an adjustment member (214, 216), which is adapted to adjust the volume of a sample section of the tank, the sample section adapted to collect the partial samples, so that there is room in the sample section substantially only for the amount of a first partial sample of a first sample, the adjustment member (214, 216) additionally adapted to increase the volume of the sample section, after the collection of the first partial sample, by an amount corresponding to a volume of a second partial sample of a second sample such that both the first and second partial samples fit in the sample section.