The idea was to add authenticity to the film.
"Kashyap was very specific with his requirements, so the production team went to great lengths to ensure that original materials were sourced from Germany, Britain and Turkey," spokesperson of the film said in the statement.
The film, starring Ranbir Kapoor and Anushka Sharma, is set in the 1960s and is a large screen adaptation of Gyan Prakash's "Mumbai Fables".
The filmmaker has ensured that everything in the film is in sync with the 1960s, and so, he had specific equipment for particular scenes. The guns were sourced from Germany, while bullets were brought from Turkey. The motion controller and blood capsules used in the film were called from Britain, read a statement.
Jointly produced by Phantom Films and Fox Star India, the film is set for release on May 15.