There is nothing quite about ANFO, and it takes some form of about a #8 booster (like 30% TNT) to properly set it off. Also, it works better at breaking rocks in a confined space, like a drill hole.
You will probably needed to provided a little more info on the whats, wheres, and whys of your project before someone could come up with a helpful plan for you.
What ever it is, good luck.
John