He was an important warrior – artilleryman and gained the rank of general field marshal.
Bärnkopp took part in campaigns in Bohemia and Silesia. He created excellent Austrian artillery thanks to it he conquered an impregnable fortress in Klodsko within 24 hours where he fought side by side with general Laudon. He was promoted to the estate of the nobility.
After peace had been concluded in the Seven Years’ War he worked as an inspector of Hungarian border fortresses. In 1772 he obtained incolate, i.e. belonging to the estates of the Kingdom of Bohemia, which was a prerequisite for gaining nobility estates and for discharging church or political office.
In 1784 he became a field armourer. He was also a holder of the highest military order – the Order of Maria Theresa.