Some screenshots taken from the Seawolf's 2nd patrol. April 1942, based in Fremantle. Patrol area is the Makkasar Strait.
This was a merchant that blew up very well after a 2nd torp hit.
Another nice ka-boom.
This one is of a Kuma-class CL I sank. I fired 2 torps, both of which hit towards the stern. She started to settle by the stern whilst moving. After a few minutes the stern was awash & suddenly there was this internal explosion (seen here) and she sank very quickly after that - vertically, stern first.