[I suspect these are not so good because they are too light. I have seen video of them in use in Vietnam. They worked for sure. And in Rhodesia someone ran some experiments with them and they showed potential. I suspect the LIGHT WEIGHT is the real reason they're not any good in the video below. But even so you'll get an idea of what they are about. Jan]

Here’s the video: https://www.youtube.com/watch?v=ZMPOGYRZ3Hw