Latest report was he now was found with ten rifles.
400 people injured, so there was you could say at least that many rounds fired. Its not hard to modify an SKS to go full auto, jam the firing pin, it will dump the mag, won’t stop till out of ammo.
Watched a video shot from in front of the stage and that area was was either concrete or pavement and it was noticeably wet. Ricochets and secondary fragment or projectiles could account for some injuries as well as injuries from a stampeding crowd. Time will tell.