What type of gun did Princip use to assassinate Franz Ferdinand ?
By the next day , June 29 , 1914 , based on the interrogations of the two assassins , Oskar Potiorek , Governor of Bosnia - Herzegovina , was able to telegraph to Vienna that Princip and Čabrinović had conspired in Belgrade with the comitaji Milan Ciganović and others to obtain bombs , revolvers , and money to kill Franz Ferdinand .