Sportvan,
I'd give you an answer to your question, but you use some confusing temperature measurement system that no body on this side of the pond understands (except for the Canadians and every single living soul south of the Rio Grande).
If my head-math is correct your 300 C. works out to a bit over our 600 F., which is a higher temperature than either the often used VHT and Duplicolor (both Sherwin Williams products) advertise as their capability. So I'd say you're good to go, as the upright apes sometimes say.