If i had my manual, i could point out the exact weight and demensions of the door, and the exact ammount of the blast it was meant to shield the inhabitants from... Oh wait, I think i can, minus that last bit... since its convieniently not in the manual. Says it has a thickness of 4 yards of solid steel, And unless my english fails on me again, i interpret that no to be the diamiter, but the distance from back to front, although in game it does not appear to be that thick, weight is not specified, suffice it to say it would be very, very heavy. I doubt even strategicaly placed c4 would do very much damage, even from withen one of the cracks. The opening mechanism would be destroyed, but the locking mechanisms would probably remain intact. I Can subscribe to the theory of drilling through the door and detenating the explosives at stratiegic points, or blowing the door off its running track while its opening. But other than the military: which includes the enclave and the BoS, super mutants, and remainging hidden weapons chashes i sincerly doubt any raiders could have gained entrance to a vault in such a way. Much easier to just bull shit the vault dwellers into opening the door.