I used to hear stories of something similar to this from VN vets. Guys would take the buckshot out of a cartridge and drill small holes through the pellets, then wire them all together and replace them in the casing in a particular pattern that would cause them to spread to the limits of the wire, so you had the penetration of the pellets and the cutting action of the wire. You never know how much of those stories were true and how much was myth.
I also had an artillery guy tell me they would fire a couple of rounds filled with Tootsie Rolls into a field, and when the gooks would walk in to collect the candy they would fire for effect on the same spot.
