Have a look at Cipher's film clip and read the Shuriken-Metsubushi thread:
shirotoratiger.proboards.com/index.cgi?board=ninjustu&action=display&thread=961
one of the Gotonpo five elements is metal - isn't this a Metal technique for escape, using a tool?
The Japanese word for Gold is Kin, so perhaps this is a Kin-waza
Bruce first turns and uses the gold as a shield to stop the first bullet - very Turtle of him (see TMNT and Troy for use of Turtle shield) then throws a bar before closing the gap - the Jumonji mutodori used against a gun rather than a sword attack
the Japanese word for Gun is Teppo and there are indeed strategies for using and avoiding firearms in later versions of some Japanese ryu - guns came to Japan very late in history but a lot of surviving traditional ryuha did adapt well to them - this was of course single shot short range guns like muskets and a lit of the concept comes from older methods of avoiding a projectile such as arrow or spear
