Board Thread:Questions and Answers/@comment-24.118.148.12-20140820044720/@comment-3250527-20140824061552

The probable Japanese pronunciation for "ballet" would be 「バレイ」 (barei) rather than 「バレット」 (baretto).

And the Light Novel translation by Yen Press has not reached Volume 8 (hasn't even reached Volume 2 for that matter). If you are referring to a fan or freelance translator, they have their own translations. However, according to the reference in Official Naming, the «Bullet of Bullets» has been written in English at least once in the novel.