300 series stainless steels are non-magnetic, or virtually so, which allows for a simple test. They machine readily to a good finish but work-harden. Modest speeds but relatively high feed-rates and DOC avoid this. Also applies to drilling. Don't let the tool rub. For myself, I'd probably use HSS tool-bits, a sharp tool is needed.
Edited By Clive Brown 1 on 24/01/2020 08:48:38