A method for collection of dry samples taken directly from a nuclear reactor core interior. Incremental samples of irradiated metal alloy components of the reactor core may be taken and collected in-situ using a specialized metal-cutting drill bit having a hollow tungsten carbide sampling cutting head, in conjunction with an angled sampling gantry. The drill bit body has an interior airflow passage in hermetic communication with a filter located in a glove box. Air holes are formed through a face of the cutting head. A vacuumed airflow through the airflow passage and at the cutting head causes a sample of any of metal chips, filings, and dust to be obtained directly from the reactor core by being pulled through the air holes and into the airflow passage and ultimately into the filter. A collected sample may be analyzed for radionuclides and radioactivity level.