Originally posted by lasersailor184
Well, pure explosives as opposed to a flash bang.
Flash-bang wouldn't open the door. Flash bang is a stun device, not a breach device.
That was a directional strip charge (why it wasn't a water tamped strip charge -- didn't look like one --- , which can be as effective with less explosives used, I'm not sure) --- which are good for breaching.
But, the concussion was obviously way more than the drop ceiling could take in an enclosed space.
And it was a big enough charge to open the whole door. There are smaller charges that can be used simply on doorknobs, locks, and hinges, which would have made more sense in an enclosed space. You can hand make such a charge with some det cord and a 1 liter water bottle.