Dont say anything but.......
I Feel you pain... on a running attack on a single DD 7 shots fired, 5 duds and 2 misses
The original poster covered pretty much everything except the angle of attack. Evidently the triggers on Mk14's will crumple without detonating if the torpedo strikes at or near 90 degrees to its target
------>| Doink !
------>/ Kaboom !
So dont strive for that 'perfect' 90 degree impact.