What type of Rasengan did Boruto used? When Boruto fires his Rasengan it varnishes. What type of Rasengan did Boruto use?
When Boruto is trying to convince Sasuke to train him, he creates a small rasengan infused with wind chakra.


  Though Boruto's Rasengan is initially much smaller, he subconsciously applies wind-natured chakra to it, enabling him to hurl the Rasengan across distances. While it loses its physical form shortly after bring thrown, the wind and force continue on-course unseen, tricking the opponent to let their guard down as sufficient damage is inflicted when it makes contact. Boruto eventually becomes able to create a normal-sized Rasengan after more training. - naruto.wikia.com/