Comments by "Dennis Young" (@dennisyoung4631) on "Naval Engineering - What happens when a shell hits a battleship?" video.

@Hyssar If I recall correctly, the batteries in those fuzes were dry charged and needed a sudden shock to break the (glass) ampule and then rapid spinning to flood the dry-charged batteries with their liquid electrolyte. This typically took a fraction of a second, hence the shell didn’t become “live” until it had gone a fair distance from the piece.
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