Torpedo range and arming distance questions

[Kavok]

Dear brothers and sisters,

Situation: May 1941, Type VII-C. Penetrated a large convoy screen and positioned myself nicely within the ranks of merchants, 7 m/s wind and clear skies in daylight (GWX on 82% realism - not important for this question I don't think).

Picked my targets and loosed all 4 bow tubes, immediately looked to see if I could get the aft tube into action as well - finding that my path to the 900ish metre off Medium Cargo was blocked by a Large Cargo crossing my solution at 200m, aft. Couldn't get a shot on that basis and, fearing the escorts, dived away under the pack to hear the satisfying 4 impacts and two big merchants heading down.

Got me thinking - torpedo arm distance is 300m, yes? If so, couple of questions....

i) Could this be reset at sea by the crew, historically?

ii) Is there any way to mod the game to amend this distance in-game?

iii) If it were possible, how far would one have to be to a torpedo blast, historically and in game terms, to risk real damage to the boat? I've been in multiplayer battles over a LAN but don't do so regularly enough to run any tests.

Regards,

KvK