Deliberate mistake: In the scene where Bond and Kananga are fighting underwater, Bond shoves the bullet into Kananga's mouth. Then, Kananga rises up and explodes. He explodes like a balloon, with not much blood at all. (01:55:00)
Deliberate mistake: The snake that "attacks" Bond in the bathroom can be visually identified as a mere kingsnake. Apparently just a black kingsnake or a California kingsnake. It is in no way venomous or dangerous but is presented in the film as such. This was done to keep Roger Moore safe by using a tame non-venomous snake. However, this breed is easily identifiable, being a kingsnake and safe, a harmless constrictor. (00:32:35 - 00:34:35)
Chosen answer: Bond just stored the bullet in his own mouth to hide it. As he puts it in Kananga's mouth he presumably pulls a pin, or forces Kananga to bite it.
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