Character mistake: When Rosie points the gun at Quarrel on his boat, she says she might have shot him. He says she might even have killed him if she had taken off the safety catch. Like most revolvers, the Model 19 .357 Magnum has no safety.
Character mistake: When Rosie sticks her revolver in Bond's room and Bond flips her onto the bed, Bond incorrectly identifies the gun as a Smith and Wesson .38 which would make it a model 10 or 15. It was actually a Model 19 .357 Magnum.
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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