I recently had a game where a damaged and prone `Mech was swarmed by infantry, who then proceeded to attack the `Mech directly while swarmed. As a result, the ammunition bin was hit which set off a sympathetic explosion in the other ammo crit locations, resulting in the complete destruction of the `Mech.
That said, however, the infantry unit was able to survive the ammo explosion with no casualties. I've reviewed the rules for ammo explosions in TW as well as the rules for Swarm Attacks and can find nothing dealing with this situation. As a swarming infantry unit can be destroyed by the target `Mech entering a body of water, I would have thought that an explosion would produce the same result, but can find nothing saying that this is the case.
Am I missing a reference here or are swarming infantry really immune to ammo explosions within their target?