That is insane that they destroyed his rifles!!! Apparently "THE GUNS DID IT!" prosecution works on more than just violent crimes now! Beautiful.
what else should the state do with them?
How about giving them back? If he wasn't actually doing anything illegal with them, then there's no reason they should be destroyed.
Thing is, a fire like that likely was not one sudden explosion of fire, but rather a small spark that smoldered in leaves or other vegetation.
Very small embers can produce very thin wisps of smoke that are very difficult to see even when looking for them. But small embers, given the right conditions, can sit for a while then blow up later, perhaps after the shooter had already cleaned up and left.