Take a look at a picture of a Typhoon and understand that the warhead of a Mk50 is about the size of your head, and you will understand why that makes sense.
The Typhoon has multiple hulls, in fact the gap between the inner and outer hulls is probably bigger than the Mk50 is long.
The ADCAP torpedoes, which are much larger weapons, are in fact designed with a two-stage HEAT-type warhead that is designed to burn through the outside hull of largers Russian submarines and then direct the blast of the second charge completely into the final hull (by reports...).
Russian submarines are supposedly designed to sustain hits from normal torpedo warheads, and so the the Mk 48 ADCAP warhead was designed to defeat these designs... or so the story goes.
Cheers,
David
PS The 360 degree Active Intercept performance is confirmed by modern submariners (Bill Nichols
).