Hypothetical 12ga Question

[Patriot]

If you put a 12ga blank in a bangstick and hit a block of ballistic gelatin, what would happen? Would there just be intense powder burns and residue along with massive concussion, or would the force from gases actually make a cavity?

[Bishop]

The expansion of gas caused by the explosion in an area of limited volume (barrel) pushes any obstructions (bullet) outward to equalize the pressure with the external air pressure. Hence, without an obstruction, all you'd have would be air rushing out of the barrel.

If you put the barrel touching the gel it should make a cavity (if it doesn't just pop or something), it should have the same effect as blasting compressed air into the gel. Burning powder will escape with the air, but it's unlikely that it will do so at a velocity strong enough to do any damage (plus it doesn't have much mass). If you do it at a range of a foot, you will basically blast the gel with air and some burning powder, doing little damage. Once the air hits the end of the barrel, it expands in all directions. The air does have forward velocity, but not very much once it escapes the barrel. That said, I still wouldn't volunteer to stand a foot in front of a blank-firing shottie :)

AFAIK! :D